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LACERTA M-GEN Stand-Alone AutoGuider - Pierro

1. Min Typical Max unit Notes DC power supply 12 15 V Active input current no light 110 116 mA 1 2 3 4 5 full light 142 mA 1 2 3 4 5 6 HC only input current no light 27 mA 1 2 full light 56 mA 1 2 6 Power down mode with USB 9 mA w o USB 6 mA ST 4 out pull down current 1 1 mA Shutter out pull down current 0 5 mA 1 3 2 light means the LCD backlight the device may draw less current due to new MCUs active meant with active Camera autoguiding or LiveView there is a 200mA fuse in the HC 1 2 3 4 the value changes as some parameters do gain exp time 5 6 the value is for the red LCD backlight Note values shown design Imaging specification of the Camera ADU means Analog to Digital conversion Unit step e means electron are only informational and derived from the RMS means standard deviation statistical Root Mean Square Min Typical Max unit Notes CCD active pixel area 752 x 582 pixel 3 65 x 2 7 mm CCD pixel size 4 85 x 4 65 um Imaging depth 8 bit Image conversion speed 2M pixel sec max Conversion min gain 1 70 e ADU 1 max gain 9 1 75 e ADU 1 Readout noise at min gain 1 20 35 e RMS 1 Readout noise at max gain 9 7 1 e RMS 1 2 4 Average dark current 3 9 e px sec 1 2 Pixel capacity 16k e 1 Operating temperature 10 60 C 3
2. the value is only informative but measured on some instances 2 at 25 C 3 violating the limits is the responsibility of the User The CCD and its environment heats itself a little bit if active good for anti dew The power dissapated in the HC is also rather useful than problematic 4 typical value mean measured on 22 pieces of random Camera instances The mean of deviation of this value between the instances is only 0 29 e The were measured in some extreme instances The gain of the CCD s analog output signal is called gain generally and can be set in the HC as a parameter The scaling of this is defined so that 2 steps means one magnitude difference in sensitivity The ful scale from 1 to 9 cover 4 magnitudes The table below shows the physical imaging parameters for each gain value approximately gain conversion pixel saturation e ADU e 1 70 0 16700 2 44 0 10500 3 25 7 6660 4 17 5 4200 5 11 0 2650 6 7 0 1670 7 4 4 1050 8 2 11 666 9 1 75 420 1 4 Tuning on and off the device After the device is first supplied with power source it goes to sleep power down mode nothing can be seen and there are no output signals The cables can be safely plugged in or out Turning ON the device Press ESC button The program will start in application mode if the HC contains valid Firmware The version of it is displayed for 2 seconds then the first screen appears
3. From 01 09 and before O O OO Adoptation from the prototype circuit and software hardware changes Indicator LEDs are now active Bugfix AutoExposure did short wake up signals periodically in wait state and much more tiny changes 10 3 About the user interface 3 1 Buttons and LEDs On the front panel of the HC there are 6 buttons and 6 so called indicator LEDs next to them The buttons are for navigation and controlling of the device while the LEDs indicates some action of it for visual checking These are the following o ESC Functions back cancel or exit Main function exiting from the current screen blue LED indicator shutter focus line active feedback default o SET Functions enter into sub menu choose set activate start editing Main function activating the selected item on the screen green LED indicator shutter exposure line active feedback default o UP DOWN arrows Functions select prev next item inc dec digit in editing mode DEC manual guiding Main function navigation between the screen s items red LED indicators DEC axis correction line s active Shows what is physically on the autoguider output o LEFT RIGHT arrows Functions changing the value of the selected item select prev next item moving the cursor in editing mode RA manual guiding red LED indicators RA axis correction line s active Shows what is physically on the autoguider outp
4. An integer value representing something meant in some unit or indexes different modes Consists of fix number of digits all these digit characters are shown inverse when selected as above in the example has limits minimal and maximal value If a limit is violated in editing mode by changing a digit s value the value is set to that limit independent of the edited digit The example above shows this type of parameter Real Real value with two digit fractional part Edited the same as for the decimal type Between the integer and fractional parts there is a dot character For example The selected AG speed RA item in this screen is real type with a value of 0 5 Time The default time type variable is always meant in 0 1 sec unit and is displayed this way For example The selected exp time item on this screen is time type with a value of 3 minutes and 15 2 seconds In editing mode it behaves as the decimal type except that some digit s maximum is only 5 ie 59 for the minutes and there are dot and double dot characters between the digits Text This type can not be edited as the other Holds a fix text or the value state of it can be changed with the SET button So the text can show the value or state of a parameter 13 Can be a so called button item that does starts some function Can be a submenu item to enter a new screen down in menu tree For example the main menu consists onl
5. see later You can skip 2 sec waiting with pressing ESC one more If the device does not contain valid Firmware or it was faulty it starts in update mode which is shown on the LCD In the center of the display there is a NO FIRMWARE text indicating the case If ESC is pressed continuously for more than 1 second the device starts in update mode Using this starting procedure is not required because the updater PC application will force to restart the device in this mode If You happen to enter this mode hold down SET for 1 second and the Firmware will try to start This works until the device communicates through USB after this only an USB command can start the application PC application has a command line option to do this From Firmware ver 1 21 or later the device starts on the date and time settings screen and the filesystem s screen after that This is needed to make You remember to set or check the correct date and time at every startup and select a file to open if You want to store data about the night guiding events etc If You don t need these functions two more ESC keypresses after startup leads directly to the main menu Turning OFF the device In application mode Navigate back to the main menu with pressing ESC some times and select the power off item It is essential to power off this way because it stops every functional part properly Camera closes the open file and stores the parameter settings
6. variable s values The current settings are stored into EEPROM memory before the replacement LCD backlight decimal 0 99 global The intensity of the LCD backlight brightness The value is used in application mode of the device the LCD backlight is always on full in update mode contrast decimal 0 9 global Contrast for the LCD By default it is 5 and is optimal in most of the cases Indicators setup submenu Here You can set the LED s brightness for each color function On this screen every LED will be lit to check their brightness in place 96 Currently the indicated events or states are constant can t be changed ESC blue shutter focus line active SET green shutter exposure line active directions red the RA autoguiding signals horizontaly left right the DEC signals vertically up down Each brightness can be next to the bright item in percentage of the full light 5 1 3 2 Mode settings screen Here are some switches for the behaviour of the functional units These are e AstroTimer mode switch profile Used to cooperate with AstroTimer shutter controller unit If enabled the Autoexposure and so the EOS shutter output signals behave differently The decription of this mode see 4 2 e Exclusive AG out switch profile Meaning of the item exclusive AutoGuiding output signals for the axes If enabled only one axis is signalled for correction at a time If th
7. 1 Screens and functions detailed Some explanation for the next screen descriptor sections and its items With blue color the item as it apperas on the screen after it in caret separated with comma if it has o type of it see 3 2 2 o limits minimum and maximum after the caret information about the storage behaviour o if nothing stays here the item value if any is not stored anywhere o global the variable item is stored at power foff but independent of the profiles o profile the variable item is a profile variable stored at power off changed by profile change For each screen description section there is a screenshot from the device right to the section title to identify the items more easily 20 5 1 1 Autoexposure AE screen To control the EOS compatible shutter output lines 3 5mm stereo jack One program can be set up at a time on this screen started paused continued and stopped The screen items are the following e Shots to do decimal 1 999 global The number of images to take in series e wait time time 0 5 99 59 9 sec global Minimal wait time between the exposures The mirror lockup is a part of the exposure This wait time could be more in real than the set value due to other functions like enabled Random Displacement The very first wait time before the first shutter exposure signal is always 1 second Note right before the end of the wait time the shutter fo
8. 5mm stereo jack ending 2m length Can be used directly for Canon EOS 350D 1 2 Powering the device In normal use during autoguiding The device needs a nominal 12V DC power source on the HC s DC input connecor which is tip positive This is essential for the Camera for imaging 9 15V is also accepted but don t use higher voltage than 15V The output power of the DC supply must be minimum 2 4W 12V max 200mA typically 2W is enough Be careful choosing the type of the DC power source it must be well stabilized or constant ie a battery An unfiltered only rectified power may not supply the device properly this could lead to sudden reset turn off of the device Logic only mode USB connection Firmware update etc If the Camera is not connected or will not be used for imaing the USB bus can alo supply the device s logic circuit All those functions are accessible that don t need analog power imaging Works for example Autoexposure program data file downloading Firmware updating but autoguiding star search LiveView etc will not When the device gets power input DC input or USB cable is plugged in a short flash of the four LEDs indicates this The flash is also present at the Firmware update process when the device is reset before the next update step 1 3 Electrical characteristics 1 3 1 Specification of the HC and Camera Note currently the is no power saving features implemented
9. can be selected but does not have any function yet The error in optimal circumtances no wind good mount is generally under some percent The orthogonality is well enough above 90 this means that the angle betweent the axes is less than 6 degrees This has almost no effect on the guiding performance even higher errors may be useful for an accurate guiding In wind using weak or overloaded mount the value could be 85 60 only It is not advised to accept them a new calibration should be started except when so bad circumstances make it almost impossible The Delete cal button can be used to delete the current calibration data It is required before a new calibration proceure can be started Note the CCD sensor s pixel acpect ratio is not exactly 1 1 The device corrects the vertical Y corrdinates to the horizontal so the pixel size can be interpreted as 4 85 micrometers and its shape as square Only the real images displayed on the LCD are not 41 corrected they could be seen a bit longer vertically due to the pixel aspect ratio and also by the LCD pixels aspect ratio 5 1 9 3 Guiding parameters page RA and DEC 3 4 and 4 4 The next two pages have the same items one page is for the RA and one for the DEC axis parameters These settings are independent These parameters define the guiding behaviour of an axis The parameters can be experienced with time and should be only trimmed later for some fix guiding c
10. details screen is shown at right The displayed data is the following State the actual state of the file that can be last opened this file was opened last time currently there is no open OPEN this is the currently opened file closed the file is closed and so can be continued reopened broken the file s data is broken can not be continued reopened O O O O Creat the date and time of its creation 29 Modif the date and time of its last opening modification If this row is empty the file was open created only once yet Size the size of its data content in kilobytes and in percentage of the whole memory rounded Downld the downloaded state of the file After downloading the file with the PC application it gets the value yes otherwise it is no Opening a downloaded file will reset this state to no value to show it contains new data appended to it The operation that can be done on the file is shown after Options e If there is no open file selecting the Open item and pressing SET button You can open this file except if it is broken e If this file is open Close is shown and is used to close the file Data storage will be interrupted Or You can go back to the files list screen with perssing ESC or activating the default Back to list item The device goeas back to the files list screen automatically also after an Open or
11. for example the last opened or a new one If You skip opening a file every function will work but no data will be saved The current version of Firmware stores only one type of data into the open file if the Autoguiding is active the guiding star s drift and the calculated correction signal length is stored This is the guiding curve currently in one huge data stream Later versions will separate these data for each exposures and the accumulated guiding star image too as a new feature Position storing without Autoguiding will give a measurement tool of PE and other The PC application will interpret and display these data in HTML format 4 5 Cooperation of the functional units The three main functional parts AG RD AE need to work synchronized if the RD is enabled This communication is shown below in a simple diagram the time axis goes downside 17 Autoexposure Random Autoguiding AE Displacement RD AG Autoguiding active Program start Requiring new position Start moving to Waitstate 77 SS ee EE S Ia Special mode Autoguiding for RD On new position Start Exposure L or E Autoguiding active Some behaviour read from the diagram e If the RD is disabled Requiring new position will fail there is no synchronization between AE and AG e The RD as a program must be enabled only at one moment the only horizontal line the movement is done using parameter values at tha
12. maximum of the 10 horizontal pixels The average mode gives the best resized image content and is smooth enough but it can suppress tiny stars that consist of only some pixels So may hot pixels also be suppressed The maximum mode is for displaying every tiny or single pixels which can be a faint star so as a hot pixel use this mode carefully Moving slightly the telescope will 35 show which pixel is due to a star it moves with the scope and which is a hot pixel stays in place e Select button Activating it a little window appears on the LiveView image inverted that can be moved along the CCD area with the direction buttons Select guiding window text is shown This window selects the guiding window s position when SET is pressed again The following of the star in it if any is started and the Guiding screen is activated By pressing ESC You can exit this selection mode The LiveView function is especially useful to roughlt focus the guiding optics If a star s big spot is made to be small enough selecting it will allow the focusing to be finalized on the Guiding screen s window in normal resolution The LiveView can be used for manual star search in some cases it may be more comfortable to do it in here than with the automatic StarSearch function If You change to the Guiding screen by selecting an area the gain and exposure time values are copied to the guiding para
13. movement rotation around the guiding star due to not enough precise polar alignment Some effect of using a noisy flat field is also smoothened by RD RD works together with the Autoexposure and Autoguiding functions if enabled At disabled state it does not affect any part 4 4 Filesystem FS As its name shows it is a data storage function of the device There is 2 088 960 bytes of free Flash memory for the files data In the filesystem there can be a maximum of 16 file entries Only one of those can be opened at a time which is accessed by all the processes for data inserting The open file stores several types of data dependent of the parameter settings to store one or more night s events to make statistics search for bugs or just check the accuracy of the autoguiding or its parameters May be used to optimize Your parameters offline The files have their own menu where details can be seen size dates downloaded state new file can be created file deleted opened or closed It is advised to download these files to PC as frequently as possible with the PC application to make enough free space for the forthcoming nights There is a date and time settings screen where the realtime clock with date is to be set This is essential for timestamping the files data to a proper identification of the stored data later After power on this screen appears after then the file menu when You can open a file
14. precisely the overexposed image will not allow to get the spot smaller than a quite big one If the spot is the smallest has some or one pixel width rough focusing is done gt Select the roughly focused star for the guiding star then You get to the Guiding screen 5 1 9 On the 1 page select max Y display mode Set the imaging parameters gain exposure time so that the star s hump could be easily seen but not reaching the bottom of the window Focus the telescope gently until the shape of the star is the thinnest and rises the most at the edges sharp If this is also done the focusing is done precisely enough You can mark this position of the focuser for later uses Note precise focus is not essential for guiding but could help increase the limiting magnitude and the position determinization is more accurate Except if You use a 44 sharp and short focal length optics because this easily maps the star into one or only some pixels that is not enough for detecting the position in fractions of a pixel In this case slight defocusing of the guiding star will help 6 3 Example for setting up and starting an autoguiding gt Navigate to the guider setup screen From main menu Guiding Guider setup gt Enter the real values into the screen s items The focal length is enough to be given roughly For the actual autoguiding speed used see Your mount s hand controller gt Navigate to the Li
15. that were downloaded to PC and then deleted The newest file is always the first file in the list at the top of the other regardless to its creation time value When there is no open file and there is space for a new one the first line will be create new which will create and open a brand new file by activating it pressing SET if selected This case is shown at the screenshot After a new file has been created the device exits the filesystem screen If there is no more space free entry for a new file this option will be missing The last opened flag L can be used to identify which file has been used previously If the device was turned off and then on open this file to continue data storage into a single file It as advised to use one file for each night if possible If a file entry s row is selected the following options appear for the buttons SET button display the file s details new screen LEFT button delete the file with confirmation This question is shown With pressing SET You can confirm the deletion while ESC cancels it If there is an open file then this screen at right can be seen there is no create new option The OP open flag shows which file is currently open The open file can t be deleted at this moment but the others can File details screen To see the details about a file press SET on it in the files list screen An example of the
16. the horizontal line Operation without ML mirror lockup 0 0 Events Start AE state Exposure line Focus line 1 set exp sec waitsec exp sec Operation with ML 22 Events Start AE state Exposure line Focus line 1 sec Ml sec exp sec wait sec ml sec exp sec 0 5 sec Operation without ML but with enabled Random Displacement Events Req new New Req new New position position set position position set AE state Exposure line Focus line 1 sec exp sec wait sec exp sec With ML the case is almost the same because ML can be interpreted as a part of the exposure state See more in 4 5 about extra waiting due to RD 23 5 1 2 Random Displacement RD screen About the meaning of RD see 4 3 Below are the screen s items and detailed descriptions e Enable switch profile To enable or disable the RD function If enabled rigth after the currently running exposure in AE has ended this generates a new guiding position for the guide star e Uniform square or Square snake text profile The used method to generate the positions The two above can be set e width real 0 01 99 99 profile The width or size of the patterns It is interpreted differently by the two modes Uniform square mode It means a quasi uniform distribution of points within a square The pattern is predefined and is designed to cover the whole area unifor
17. will follow the star with repositioning the guiding window even if the autoguiding is not started Because of this the monitored image of the guiding star within the 48x48 pixel window may be shown as replaced immediately but this does not affect anything it is only made by display This star following is a part of the software can t be turned off If the followed star is lost gets too dim by clouds or jumps out of the guiding window by a mechanical push the guiding window stays and waits for the star appearing again in it no automatic re search is done The user may search for the star again with Live View or Star Search This could happen often if You touch and push the mount telescope or the DSLR by hand and it is not stable enough After this the star may stabilize in its old position in guiding window but the window may be repositioned as it wanted to follow the star and that s why the star is lost This is done the same way if the autoguiding is active but the device tries to correct the position if there is any If the star is lost temporarily no autoguiding signals are put out At permanent star lose no automatic re search takes place o If You started to use the Camera once do not just pull out the Camera cable for example to detach the Camera from the guide scope Stop the Camera before which can be done only with powering off the device currently ae The Firmware handles the lose of the Camera bu
18. 16 4 4 FIEES YSTEM A se SAE E E E A 17 4 5 COOPERATION OF THE FUNCTIONAL UNITS 00ccscscssssscssscscscsssessscscsesesessssseseseseseseeeseseseseseseseaeaeaeees 17 5 A A DADA HA D EE E EEEE E TE REEE T E A EEEE E 19 5 1 SCREENS AND FUNCTIONS DETAILED cccccccscecscecececececeeeeecececeeeeeeeeeeeeeeuseeusuauaeeuseauauauauauauauauauaeananaes 20 DLA AUloexpOsure AE Bereet e AER EE RE Wate cez sd vaya Ae Ee ee 21 5 1 2 Random Displacement RD screen ccsscceseceessecesseeessecesneeeseceseeeessecseneeesseceeneeesaeceeneeesaeceeneeenaeens 24 5 1 3 IVITS CS CVC EE 26 ILA lt POW EE 30 ILO GUIING MENU screen ns oser has ed Meenas Gis AE 31 D120 EE 32 GE E EE EE El tee e e le teg EEEIEE EEE Sal ee ee 33 5 1 8 PAVE VIEW SCT CCI uss ug Bae oe E Rese hea cess e E ee SI Ed 35 KSC Guiding EE 37 6 INTERNA DN EE A4 6 1 ASSEMBLY AND SAIT a de dahate dudecenode a betel dua a e a a lea oaen 44 6 2 FOCUSING USING LIVE VIEWS EEE T EAE E E E E EE A E EET 44 6 3 EXAMPLE FOR SETTING UP AND STARTING AN AUTOGUIDING sssssssssesesesesesesrsrrrsrrrserrserrrrrerererereerrere 45 7 ERROR CODES issssiscsesctictvccssssovcssssccssssisiecssvebsesssiessesescessessssesiesestceds sesscesesees sovessodeviecsosendecsdessiessbbieesses 47 8 PLANNED DEVELOPMENTS E 48 1 About the Hardware 1 1 Parts of the device The LACERTA M GEN Stand Alone AutoGuider referenced as LMG consists of the following parts e Handcontroller referenced as HC I
19. Close operation 5 1 4 Power off screen This asks for power the device off SET or not ESC Power off makes everything go inactive This is the advised mode to stop the device before plugging out power cable s because it closes the open file if any saves the parameter settings stops the Camera properly etc There is a half a second dead time before the device gets any button press to avoid unwanted power off With ESC You go back to main meu 30 5 1 5 Guiding menu screen This screen and its subscreens holds all the functions and settings for autoguiding e Current guiding subscreen This leads to the main Guiding screen 5 1 9 1 e Live View subscreen To enter Live View screen where the full CCD surface can be monitored in realtime e Star search subscreen Leads to the automatic star searching function s screen Compared to the Live View this is more immune to single hot pixels and finds faint stars e Guider setup submenu Holds the parameters of the guiding optics and the mount s autoguiding settings eee 5 1 6 Guider setup screen This screen holds the parameters of the guiding optics and mount so guider in this context does not mean the autoguider device These values are needed by some function that does not know anything about the used system and giving the values approximately helps them Calibration is such a function e Obj focus decimal 50 60000 mm profil
20. D from Sony with ExView HAD technology Due to its exremely low dark current dark noise and the enhanced sensitivity in near infrared it doesn t need cooling and saves energy These with the low readout noise gives the ability of guiding on very faint stars or using small guidescope The small pixel size allows using shorter focal length for guiding compared to other systems For more information see the datasheet of the CCD its part number is ICX279AL E Some info can be found here http www sony net Products SC HP datasheet 90203 data a6805282 pdf Note ont the CCD there is the protector fiol by default You must remove it before the first use Cleaning the CCD s glass is done as for any other optical surfaces Try not to scratch it Don t let any electrically conducting material or liquid fall into the circuit on the CCD and its pins The foam around the CCD gives some protection e Supplied cables o l piece of Camera cable black similar to a straight UTP cable Used to connect the Camera with the Handcontroller It s length is around 1 8 2m o l piece of ST 4 autoguider cable white to connect the Handcontroller and the mount with ST 4 compatible autoguider input About 1 5 meters of length o 1 piece of USB A PC side USB B mini5 HC side cable to the connection with the PC Used to update Firmwares download data files or control the HC o Some release include an EOS shutter cable with 2 5mm and 3
21. LACERTA M GEN Stand Alone AutoGuider User s manual for Firmware 01 22 Created by Zolt n Tobler at 9 J une 2010 Last updated 21 J uly 2010 Table of contents 1 ABOUT THE HARDWARE ise cc sssscuscssusssssccbesseuscssseewssussseuceessesecs teusoucesbecesssscsev sebceseduuscdes SEE Saras s TEST 2 1 1 PARTS OF THE DEVICE ee OER RE 2 1 2 POWERING THE DREES 4 1 3 ELECTRICAL CHARACTERISTICS EE EE 5 1 3 1 Specification of the HC and Comerg 5 1 3 2 Imaging specification of the Coamterg 2 1 4 TUNING ON AND OFF THE D NICE 6 2 NEW FEA TURES IN FW TV E e E 8 2 1 PREVIOUS VERSION CHANGES ssssssseseseseseseseseserertritttttttttttttttt ttrt tt tttEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE EErEE 8 3 ABOUT THE USER INTERFACE esseoeessecessseesscceesseceesseceeececsscoeesseceesoeceessecsssoecssooeesseceesseessoseessooeessecee 11 3 1 BUTTONS AND H D s EE 11 3 2 MAIN CONCEPTION OF THE USER INTERFACE 0 00sescscssssscscscscsescscsssscscssssscsssescssssscssssessesssrststsneeaes 11 3 2 1 NVC TUS os Pe Sick Sek aa ces nee eed Men ba Ook SNE ASRS ed ULSAN a ey HPI ERLE AE ES 12 3 2 2 Wd riabl es parameters onc ee enee ere EES ab ted hase obec eat tavatnty yew S 12 323 o TEE 14 4 PARTS OF THE SOFTWARE FUNCTIONAL UNITS u ssccccssssccssssscccssssccccsssccsssssccccssssccsssssesceses 15 4 1 AUTOGUIDING FUNCTION AG erana Genee Ee e E a e the Bees 15 4 2 AUTOEXPOSURE FUNCTION AE 16 4 3 RANDOM DISPLACEMENT FUNCTION RIDE
22. WARNING simply plugging out the power cable is not recommended mainly if the Camera is actively working Data loss or corruption in the open file or in the stored parameters may occur If the device is in update mode and there is no operation in progress mainly Firmware update You can power off the device with detaching the power cable s Be sure there is no operation in progress shown by the PC application WARNING never plug out the power USB calbe during Firmware update Doing so can damage the boot program and it may be required to reconfigure the device at factory it s not the part of warranty 2 New features in Fw 01 22 A short list about the main features compared to the previous one 01 21 o The AutoExposure s state and outputs are also stored into the open file The guiding curve drifts is saved only when the AE is in the exposure state It belongs that the PC application version 1 22 generates a HTML format output when downloading a file which contains for all the exposures separately the guiding curve as well as the spread of the guiding star positions and the approximated tracking error of the mount derived from the autoguider signals All the raw data is written into a CSV file for any user processing o The calibration has been moved to a new screen on which the directions speeds and the orthogonality is displayed o When starting the autoguiding the latest position is not rounded to pixel center
23. a value of 10 is useful and is above the readout noise at any gain If some pixels randomly appear at the edge of the star gui mask display mode increase this value until the star s edge is no more noisy If there is a fainter star close to our guiding star this threshold can be also increased until the faint star does not appear even for a moment This is not advised if the difference of their brightness is less than about 2 magnitues AG start or AG stop button To start or stop the autoguiding When starting the latest star position will be the guiding center where the star is to be held Later the guiding center can be overwritten with a new value for example by the RD function The position is always a fractional any subpixel position is allowed The autoguiding can t be started if there are no star pixel in the guiding window lt lt button The display mode of the window at left is changed by this item presing SET on it see display modes at 5 1 9 pg A button By selecting this item and pressing LEFT RIGHT or SET the active page of the Guiding screen can be changed This item can be found on each page at the same position 5 1 9 2 Camera orientation and calibration page 2 4 The Calibration s function is to determine the relationship between the sky axes and the Camera coordinates and the actual correction speeds for both sky axes It is required to make the device know how th
24. amera went critical too low or high failure in the power supply unit of the HC CAM error 03 Camera is not connected with the cable Camera cable contact error or not connected CAM error 04 Other Camera connection error Camera cable or Camera failure CAM error 05 Initializing communication with the Camera failed Camera is not working properly or is in bad mode CAM error 06 Connection lost with Camera unknown error the Camera is stopped somehow suddenly CAM error 07 Firmware version mismatch HC and Camera Camera has an other verion of Firmware program than the HC needs The Camera can t be used ERR type 90 Timeout during calibration communication was interrupted somehow with Camera ERR type 51 Star lost error The star was lost during a procedure because of clouds or wind blow ERR type 82 Calibration interrupted by the user ERR type 81 Coarse position error during calibration if the position is way too off from the expected Badly set guider parameters focal length and AG speeds ERR type 83 Orientation is inadequate during calibration 47 8 Planned developments The Firmware for the device is continuously developed There are planned functions that are not implemented yet so are missing from the current Firmware The direction of the development is influenced by the feedbacks from the users and the testers Currently the following useful functions are planned to implementat
25. ation until an acceptable orthogonality is measured over 90 is near perfect gt Change to page 3 and 4 5 1 9 3 and set up the guiding parameters for the axes as advised gt Change to page 5 1 9 1 and start the autouiding Soon the first correction signals will be indicated by the red LEDs as short or longer flashes By monitoring these signals You can trace what the guider is doing If Your mount has some typical errors as mine has those can be observed easily by watching 45 the LEDs If these LEDs are flashing sometimes rarely the autoguiding is working well You may discover and keep off many symptoms like o Oscillation The LEDs in the opposite directions along one axis will flash alternating left right left and so on for example o Backlash stucked gears or ST 4 cable contact error one LED flashes almost constantly in one directon and it never ends o Etc 46 7 Error codes In some cases there are error codes generated in the device These may not be fully interpreted yet in the current Firmware and displayed as a text but the error codes are These are the following with a short description of the cause ERR type c0 Indicates Camera error CAM error 40 DC input power is too low or missing for the HC some below 9V CAM error 01 Some analog supply for the Camera is too low failure in the power supply unit of the HC or in the Camera CAM error 02 Some analog supply for the C
26. but used the raw position directly for the new guiding center 2 1 Previous version changes From 01 21 o The menu structure has been changed a little bit Some rarely used screen and parameter is pushed down the tree while for example the guiding screen is now accessible with only two SET keypresses from the main menu o Complete file system menu screens open close delete and create new a short file list and file details screen The date and time settings screen is also accessible now from menu o In Autoexposure selecting Start Stop Pause will change the selection to the more understandable item o LCD contrast can be set and is stored o AstroTimer mode the Autoexposure s and Random Displacement s opertion mode using an external shutter controller device This mode is fully compatible with AstroTimer The Autoexposure will have only one time value period to set while the external shutter is active and the shutter output will be only active when a Random Displacement is being made the AE program is in wait state o New RD mode besides the default uniform square there is a new square snake pattern o Exclusive autoguiding output signalling mode Non simultaneous signalling Only one axis can have autoguiding signal active at a time that s why it is called exclusive mode Between different axis signal there is a 62ms dead time This BER may be used with old t
27. cus line is active for the last 0 3 seconds to wake up the DSLR if it was in standby e mirror lockup time 0 20 0 sec global Mirror lockup means if the DSLR has a mirror lockup option and is active it will only move the mirrors out of the optical path for the first shutter signal and the next signal will start the real exposure The lockup of the mirrors can cause the telescope mount to oscillate for a short time If ML is activated in the DLSR this must be also set up in the device to be in synchron This item is to do this The mirror lockup time is always 0 2 second then the device is waiting in the remaining time If this item is set to 0 0 it means the ML is disabled Note independent of the value set the ML time inluding wait phase is at least 0 5 second except if disabled 0 0 e exp time time 0 1 99 59 9 sec global The desired exposure time e Start or Stop button Used to start or stop the program At stopping the program is interrupted regardless to its current state and the shutter lines go inactive immediately It is possible to stop the program while it and the DSLR is in ML state In this case they will be out of synchron but the DSLR may timeout from ML state and the synchron is okay from that time e Pause or Continue button The program can be paused in the wait state between the exposures This item is only shown when the program is running If Pause is activated a P charact
28. dard correction speed can be set o The drifts history diagram is now displayed scaled to the tolerance value o Pause Continue button added to the AutoExposure screen during paused state the AE program parameters can be changed o Additional wait time can be set between the guiding exposures letting the mount to react before the next exposure Useful to lower the chance for oscillation will be obsolete using the smart guiding method implemented soon From 01 11 o New drifts as a guiding display mode the history of the drifts of the guiding star can be monitored for the previous 48 frames o Increased LCD backlight PWM frequency it has no effect on the Camera now in LiveView had a tiny o Bugfix Camera stop in cold symptom has been corrected in hardware too From 01 10 EL O ECH CHE O LiveView function 1 10 size real time image for the entire CCD field Te threshold parameter is now set in pecentage Sme parameters can be changed with LEFT or RIGHT buttons too Avanced method for StarSearch overexposed stars are missed more rarely Te brightness of indicator LEDs can be set individually Asking for stopping the guiding if it s in progress and some function needs to have it stopped Autorepeat for all the buttons makes the navigation or parameter change easier A 0 5s dead time for the buttons is inserted at the power off screen to avoid accidental power off of the device
29. e mount will react on the autoguider signals and know how the guiding star will move on the CCD This screen contains the main elements of setting this camera orientation data The screen items are the following 39 e Invert RA invert DEC switches When enabled they invert the apropriate axis autoguider signal direction It is important to know that these inversions are made just before putting them physically to the output and so they will invert all the signals generated by any part of the unit If a calibration data is used these need to be disabled Inverting one of them may be necessary after a meridian change of the mount pointing to the same point of the sky but physically differently At manual autoguiding setup when the Camera s horizontal X axis is parallel to the RA of the mount this can be used to set the polarity of the image For example using a mirror will need one axis to be inverted e Manual button By pressing it the autoguider signals stop and the direction buttons can be used to control them manually On the screen a MANUAL ESC to quit inverted text indicates this manual control mode You can exit this mode with pressing ESC May be used for checking the axes directions or for maunal guiding for some purpose e Calibration submenu Enters the Calibration screen to show and start or delete the current calibration data 5 1 9 2 1 Calibration screen The screen displays all of
30. e The focal length of the guider optics used with the Camera in millimeters e AG speed RA DEC real 0 00 1 00 profile The correction autoguiding speed relative to sidereal rate set in the mount s controller Any non standard rate can be set with 0 01 step size The RA speed can t be set under 0 01x while for DEC it is allowed and means that DEC speed always equals RA speed See the screenshot for the case Changing the values take effect immediately if no calibration is in use If there is no calibration data the operation mode below is active Axis aligned manual setup If You want to set up the autoguiding manually You can skip using calibration In this case this screen s values give information about the actual correction speeds The RA direction must be horizontally X axis and the DEC vertically Y axis aligned The actual RA speed spdra changes as a function of the object s DEC coordinate DEC This RA speed must be calculated and set up by the user manually The formula is the following span spdra cos DEC Se 5 1 7 Star Search screen After setting some guiding parameter that You want to use an automatic star searching function can be started from here The guiding parameters are the imaging parameters like analog gain and the guiding exposure time This two main parameters are responsible for the limiting magnitude and the precision of determining the star position These values are
31. e device wants to signal both axes the RA will be signalled first and the DEC after then in other words the RA axis is in priority to the DEC Note it may occur that the correction guider imaging frequency is so frequent that both of the correction signals could not be put out fully In this case the new correction signal gets active and the current is interrupted It may delay the DEC corrections if the RA must be corrected continuously Note there is a 62ms dead time between the two axes signals to let the circuit of the mount to react on them 27 5 1 3 3 Date and time screen You can set the realtime clock and date here The format is displayed on the screen year month day and hours minutes The seconds are also displayed but can t be changed After setting a new date the device checks it and limits the day value Always recheck the displayed date after changing it This screen apears right after power on from Firmware 01 21 If the filesystem is to be used set the date and time properly timestamps will be instered into the file Note changing the date ant time items takes place immediately If a file is open and data is being stored into it the timestamps will change suddenly causing the data flow getting a bit confused Only set a new date or time when no file is open or do it properly only once after power on 5 1 3 4 Filesystem s screen s This screen is for showing and controlling the files After sta
32. e external shutter device must wait In this mode there is only one parameter that can be set the time period between two RD movements It is shown as the exposure time of the program 4 3 Random Displacement function RD Also known as dithering It s goal is to move the telescope with relocating the guide star randomly between the imaging exposures avoiding to image the object time to the same sensor surface each time This has several advantages Some untouched or termporary hot pixels can be eliminated automatically at the combination averaging of the single frames These pixels will be located at different position on each frame relative to the object after registering alignment Similar to this overcompensated pixel caused black holes are eliminated also and the noise effect of wrong dark frame subtraction is smoothed The non uniformity of pixel sensitivity causes extra noise pattern that can be suppressed smoothed too Using very short focal length objective and a sensor with Bayer matrix color filter can cause false coloured star spots as they are easily imaged into a single pixel By moving the image over the filter matrix will lower this color noise 16 On photos taken without RD some small pattern of the background noise is a typical effect This may be caused by the changing gravitational flex in the system using a guide scope and a separate imaging telescope or image
33. een They are identical changing one makes the other change too See at 1 3 2 xp decimal 50 4000 ms profile The same variable as the expo time at Star Search screen this is the exposure time They are identical changing one makes the other change too Note the frequency of refrshing the Live View image can be higher than it would by the exposure time set This is because reading the 10x10 pixel field is done with 10 rows added in hardware and therefore it is more sensitive than at normal resolution So the used real exposure time in LiveView is always shorter than the desired value but shows the same sensitivity as would at autoguiding thr decimal 1 99 Threshold value to discriminate the resulting pixels for display The percentage is meant to the 8 bit depth 50 will mean 128 The used threshold value is calculated by an addition of the minimal value of the full LiveView image and this thr variable s value Generally a low threshold value can be used to show faint stars but not the background noise On the screenshot above only the background noise can be seen avg or Max special switch As written above each resulting dislpayed pixel is derived from a 10x10 CCD pixel field The 10 rows are added in hardware but there are different modes of processing the 10 horizontal pixels values and the resulting pixel value will be avg the average of the 10 horizontal pixels Max the
34. er at the left bottom part indicates that the program will be paused after the current exposure SE ended The item text will be Continue The paused state gets active at the last 0 1 second of the wait state of the program At the paused state the program variables can be changed Meanwhile a running program it is not allowed The remaining time will stay at 1 second at paused state Activating Continue will clear the paused state or the signal to pause before the next exposition If it was in paused state the next exposure starts immediately Note if the RD function is enabled the next movement is started before the program reaches paused state If an AE program is running the bottom line there is information about the current state oat left one character showing the current state of the AE program w wait time is counted down m mirror lockup time is counted down E exposure time is counted down and the next one the actual physical shutter signals nothing both shutter signals lines are inactive O only the shutter focus line is active both lines are active o on the middle the next or current exposure s index and the exposures to do although it can be read above at the item o atright the remaining time of the current state in seconds rounded up Below there are some example diagrams for the running of the AE program in different cases Time axis is
35. examples 6 1 Assembly and startup gt Fix the Camera to the guider telescope or other optics Try to put it near in focus gt Connect the cables advised in this order DC power cable into the HandController nominal 12V can be charged Camera and HC with the black 8 wire cable UTP like The mount s ST 4 compatible autoguider input and the HC s output with the white 6 wire cable Then the DSLR and the shutter output of the HC Note don t plug the ST 4 cable 6 wire into the Camera port 8 wire because the connector may bend the two extra connector pins at the sides and so the Camera will not be accessible by the HC This is why the order of the assembly should be followed The bended pins could be repositioned but needs some practice doing this gt Turn on the device press ESC gt Set the current date and time exit the screen and open a file If You don t need data storage press ESC again 6 2 Focusing using live views gt Set the guider telescope to a bright star above 5 magnitude must be enough gt Navigate to the LiveView screen 5 1 8 From main menu Guiding Live View Set the exposure time for some seconds the threshold to a low value 10 for example Increase gain until the defocused big spot appears on the screen After this focus the scope until the spot gets the smallest possible As the star closes to focus You can lower the gain and or the exposure time to be able to focus more
36. hown right next to the frame with two short lines the size of it is 2 pixels to the zero As the tolerance value is changed so changes the appropriate axis drift diagram s scaling This diagram is called guiding curve too Note the screenshot example does not show a real guiding curve on a star but on the background noise only At the top left of the screen there is a counter increasing or staying between 0 and 63 This is the frame number from the Camera If it is changing time by time the Camera is working following a star or nothing If the counter is still the Camera does not work in guiding following mode or is not powered so don t expect any reasonable image In the guiding window that means also a 48x48 pixel area on the CCD surface there must be only one star at a time or maybe some close doublets Stars appearing partially or temporarily in the window will disturb the position determination so choose stars that have no other close to them almost with the same brightness You can check this at the automatic Star Search but even at Live View Modified star following method will be inserted in later Firmwares as an option to avoid such cases The guiding window follows the actual star in it as written earlier If the star closes some edge of the window the window is relocated to center the star in it This star centering happens some time ie during the calibration procedure Don t bother with it it ha
37. ion not all listed e Besides the guiding drifts every other events to be logged into the open file For a more readable statistics of the night s e Automatic image processing at Guiding Some variables like threshold will be automatized to free the user from taking care about them The option for manual setting will be held A new method for following and determining the star s position Close bright stars will not affect the evaluation of the followed guiding star Along with this the real guiding image window size will be increased to follow the star more accurate to lose it less probably e New guiding method optionally selectable a smarter method that consideres the mount s theoretical reaction and its movements made for the previous autoguider signals So it compensates predicts many things in the system and lowers the chance to parametrize an axis causing oscillation e Advanced Star Search function that makes automatic imaging parametrization after the search and chooses the most useful star in the field May offer an optimal guiding parameter setting in each axes for the selected star e Extending the Calibration function separate window displaying the current calibration It allows to calibrate only for the correction speeds to save time if the Camera is not rotated Optionally orthogonalization of the resulting direction vectors If these result far from optimal every time orthogonalization might hel
38. meters as well as the threshold value but this is set at a minimum value of 10 avoiding background noise surely Note there is some higher dark current present in the vertical register of the CCD that affects the read image The rows have growing offset This is compensated by software and that s why some horizontal pattern steps may be seen on the LiveView image at low threshold values Don t bother with it it won t affect guiding performance 865 5 1 9 Guiding screen One of the most important screens is this one From here You can start stop parametrize the autoguiding run the calibraton etc Due to the much function and parameters this screen is splitted into pages that is displayed at the right bottom as pg 2 4 Changing the page is done with this item LEFT or RIGHT SET buttons On the Guiding screen there is always the guiding star or other monitored in the window on the left This is a 48x48 pixel window in a frame Below the frame its content type is shown which can be one of the following Changing it is done with the lt lt item next to it e gui mask The image of the guiding star Those pixels are shown lit bright that belong to the guiding star and are involved in the calculation of the star position This image is a real sized part of the CCD This display mode can be seen at the screenshot above showing only a background noise Note due to an automatic ho
39. mly even at low number of exposures The width stands for the width of the square s sides the unit is pixels in the Camera Note the physical pixels are not exactly square shaped so the Y coordinates size are scaled to be equal to X which is the horizontal axis For example width 16 means a 8 8 pixel interval for each axis relative to the autoguiding center where the AG has been started Square snake mode This pattern is not random but the pattern shown at right It steps on a square grid the step size is always the same The first step is to right RA axis and the next steps are counterclockwise around the previously used positions In this mode width is interpreted as the grid distance or one step s size This has an other scale than the other mode be careful and check the size every time You change between the modes Knowing the directions of RA and DEC axes the generated position are mapped to this coordinate system so X movement will always mean moving in RA Y will mean moving in DEC Each new guiding position coordinate is limited to 16 pixels close to the CCD surface s border to avoid star lose 24 A new displacement is generated by the Autoexposure program when it goes into wait state In this case the AE waits until the new position has been stabilized and continues the program after it see the example at the end of section 5 1 1 The RD positions are fix so reproducable The positions a
40. on profile global variables are not affected by a profile change The parameters of the AutoExposure program are of this global type for example Profile variables are generally for those variables that are needed for autoguiding 14 4 Parts of the software functional units There are some well defined functional units in the device In the next sections You can read about these functional units for the sake of a better transparency 4 1 AutoGuiding function AG The main function of the device is Autoguiding It has its own process runs independently of the other including the User Interface handling the Camera is it s job exclusively so the program of the Camera is the part of this functional unit The guiding star s image is processed by the Camera The guiding program in the HC uses the calculated star position to control the mount with the ST 4 compatible autoguider port There is a dedicated screen for Autoguiding on which everything can be controlled that directly affects guiding This is the guiding screen can be reached with two SET keypresses Main menu Guiding Guiding menu Current guiding Guiding screen is indicated by a cur text in the top right corner and a 48x48 pixel window monitoring something on the left of the screen There are more pages of this screen more on this later Important notes o If the Camera is active and there is a star in its guiding window an area on the CCD field it
41. ond the typical value is 70 100 using shorter correction frequency requires to lower this value to overcome oscillation around the zero drift point Be careful not to chase the seeing use as much integration time as your mount s errors allow mode decimal 0 2 profile Some different guiding policy is available this can be given by this item These are 0 Inside the tolerance interval there will be no correction signal but outside of it the device will try to correct the drifto to zero 1 Inside the tolerance interval there will be no correction signal but ade outside of it the device will try to correct the drift back to the tolerance border only 2 The same as mode 0 but this singals even inside the tolernace border as a function of the current drift to remove low frequency component of the guiding curve the drift s history This mode is more liable to cause oscillation it may be compensated by lowering the aggressivity or increasing the tolerance a little bit There is an emergency action for both axes If the drift is beyond 3 times the tolerance limit the averaging is turned off and correction signal is generated immediately This is for the case that the star is suddenly moved out of its position and is needed to get it back to zero drift as fast as possible Other causes can be wind backlash and mechanical errors in the mount Currently this emergency behaviour is always active el 6 Practical
42. onfigurations The items for an axis Num decimal 1 99 profile The number of frames or star positions that should be averaged before a new correction signal is calculated and sent to output With this item it is possible to lower the correction frequency or to increase the effective integration time For the RA axis this value is generally 1 causing no averaging and calculating correction signal after each new frame For the DEC axis the averaging may be used because there must be only low and constant drifts here Averaging avoids chasing the seeing on DEC tol real 0 01 9 99 pixel profile Abbreviation for tolerance This is a threshold value in both directions to the center zero drift that means an interval in which the device handles the drift with tolerance There are more modes of behaviour inside the tolerance interval which is described later aggr decimal 1 200 profile Abbreviation of aggressivity This is a scalar factor that multiplies the calculated correction signal s length This item trims the guiding strength avoids oscillation and compensates other anomaly a wrong calibration if set carefully At manual guiding parametrization no calibration data is present this allows the User to set RA correction signal lengths according to the objects DEC coordinate That s why the value is allowed to be over 100 Note with calibration using long exposure time over 1 sec
43. ouchy mount that don t tolerate the default parallel signalling o Bugfix quitting from LiveView screen did not stop the imaging into the screen o Bugfix in some special cases the guiding image was drawn into false position even if it was inactive From 01 20 o Stepping back in menu tree will hold the priously selected item It s easier to re enter a screen if You had left it accidentally o The method of calibration is modified now it s more immune to temporary star lose position evaluation bettered and the result s precision axis direction is displayed o Modified RD method it does not move the guide star to an exact position instead it moves it only close to it to minimize the dead time between the exposures that was rather long in wind or at bad seeing parametrization o Real time clock 0 1s resolution and date to timestamp the data stored in the open file o Basic filesystem and selection only at startup The open file will store the guiding drifts and the calculated autoguider output signal lengths To download the files use the PC application v1 22 o Bugifx some more byte parameters were not stored correctly at power off From 01 12 o Three profiles available now to store parameter settings individually Can be used as presets for separate guiding configuration off axis guide scope s etc o AG speed can be set independent for each axis with 0 01 step size any non stan
44. p the wrong calibration data to be much more useful e More user friendly interface all errors handled and displayed as a text easier navigation between the main control screens and more comfortable parameter value editing e Optional power saving modes implemented Currently there are no such modes working in the Firmware but the dissipated power is not too high In cold it works as an anti dew function Power saving may reduce the required power noticeably 48
45. re indexed in the device that starts from 0 at power on This first position offset is always 0 0 Later the index grows but can t be reset to 0 currently If You stop the autoguiding and restart again remember that the star may be located somewhere but not where it was at starting the autoguiding In this case the autoguiding center changes and the new RD movements are done around that point The display of the RD positions prev and next ones and the ability of changing the position index will be included in a later Firmware version The RD movement is not done exactly The new position may differ from the calculated one a little bit This behaviour is to save time at RD movement letting more time for the exposures SEI 5 1 3 Misc screen This screen holds every menu and settings that may be accessed rarely 5 1 3 1 Display settings screen The LCD and LED indicators settings are here Display submenu Leads to LCD and LED indicators settings Mode settings submenu This submenu contains switches for the different modes of operation of the functional units Time amp Date submenu The realtime clock with date in the device can be set up here The filesystem uses this for timestamping File menu submenu Handling the files in the DataFlash memory is done from here Active profile decimal 0 2 global The currently active profile s index Changing this value will replace all the profile
46. rtup and the date and time setting screen this screen appears If You don t want to store data into file press ESC again to exit into main menu The meaning of the files can be found in 4 4 Files list screen the screenshot above There can be 16 file entries at a time The list of the used file entries is shown in the first 6 rows of the screen If there are more than 6 of them the list could be scrolled an up or downward triangle shows on the left where the list can be srolled The content of the rows Date and time of creation Might makes the identificaton of files easier At right optionally a sign about the state of the file These can be o L this file is the last opened one there is no open file o OP this is the currently open file o the file is broken has error Can not be opened but a part of its content may be donwloaded This can occur when an open file has not been closed or written properly for example at a sudden power loss Checking the type of the error the PC application can be used At the bottom above the functions of the buttons the free memory is displayed in kilobytes and in percentage of the whole memory This is not refreshed shows the state at entering this screen 98 The files in the list are ordered by their unique ID This value is constantly increasing with every new file creation and gives the ability to indentify all new files from the older ones from even those
47. s no effect on the guiding This star following behaviour is always active until the star is suddenly lost somehow or the star drifts off the CCD surface 5 1 9 1 Main imaging page 1 4 This page contains the parameters of imaging and the autoguiding can be started and stopped from here Currently only this page allows to change the display mode in the guiding window on the left The screen items are the following e gain decimal 1 9 profile The same variable as the image gain at the Star Search screen They are identical More on this value at 1 3 2 Changing the value takes effect imediately at the next exposure e exp decimal 50 4000 ms profile Ce The same variable as the expo time at Star Search screen They are identical The used exposure integraton time for taking images for autoguiding wait decimal 0 250 ms profile Wait time between the guiding exposures The mounts reaction time is never ideal for the autoguider signals If there is a bright enough guiding star this wait time can be used to wait some until the mount can react Using good guiding parameters and later anew guiding method this value can be constantly 0 thresh decimal 1 99 The threshold value to discriminate star and non star pixels The value means the percentage to the saturation relative to the background pixel value the minimum of the noise suppressed background for each frame Generally
48. t has the whole user interface buttons indicator LEDs LCD and does the main functions like Autoguiding Random Displacement AutoExposure etc The display is a graphic 128x64 dot negative LCD with backlight Previous versions have red while the new ones come with amber orange color due to the much better contrast or A l Laam LACERTA AGEN J The connetor panel is located at the bottom of the HC box These are the following from left to right o Canon EOS compatible shutter output 3 5mm stereo jack conn o Camera port RJ 45 type female conn can be used any low resistance UTP cable too but the supplied cable is preferred Note NEVER try to use a UTP cross cable o DC power input 5 5 2 1mm size 12V nominal 9 15V tip positive polarity protected o ST 4 compatibles autoguider output RJ 12 type female conn o PC communication port USB B mini 5 pin conn e Camera head This is a special device can be used only with the LMG Handcontroller It s function is imaging and doing several image processing steps To attach the Camare to the guider telecsope there is a 4 S5mm thick T2 inside screw Any T2 1 25 adapter can be used for 1 25 31 7mm focusers There is a 1 25 filter thread inside the T2 panel to attach some filter or dust preventor At the back of the Camera there is the same type of connector as on the HC RJ 45 female The sensor is a high sensitivity monochrome CC
49. t it is not safe to power off it that way it might damage some circuit part in the Camera 4 2 AutoExposure function AE The Autoexposure functional unit is also a separate part of the software On its dedicated screen can be set up started and stopped etc The shutter signals generated by this functional unit appear on the 3 5mm stereo jack output connector and can be directly connected to a Canon EOS 350D or similar DSLR with such a shutter input open collector line The AE s function is to shutter Your DSLR synchronized with the device s functions The AE program runs totally independently of the other units by default In this case it can be used as a single automatic shutter device too can be powered only from USB as well The only case when the AE is synchronized with other functional units is the Random Disaplacement function enabled and the Autoguiding active The shutter program has two operational modes o Normal mode default all the shutter program parameters can be set and used wait time mirror lockup time etc the DLSR shutter is controlled fully by the LMG device AstroTimer mode this mode is mainly for cooperating with the external shutter device called AstroTimer but other external device may be used In this mode the device does not generate shutter signals but other the shutter output is only active when the Random Displacement function is moving the telescope so it indicates the time when th
50. t pixel suppression single hot pixels are not shown in this image and so don t disturb the guiding e maxyY A vertical profile of the raw image The maximum pixel value of the columns of the raw image is calculated and shown in a diagram The zero dark level is near the top and the saturated pixel level is on or near to the bottom The screenshot shows a single hot pixel causing one column to be saturated The other columns does not contain hot pixel so they only show some background noise Note the diagram is NOT a histogram but a vertically projected map of the raw image This mode is used to trim the focus precisely If the diagram shows a wide hump the star may be out of focus The focus is the best if the thickness of the hump is the smallest and the rise of the sides are the highest Note using long exposure time more hot or warm pixels could be on the raw image and so in this dislpay mode too If these are located far from the guiding star and can t be seen on the gui mask mode they don t affect guiding e drifts This is a time diagram or history of the drifts of the guiding star realtive to the guiding center where the star care should be held The latest 48 drift values are shown for the latest 48 frames for each axis One time step one frame is one pixel horizontally while vertically the drift values are scaled to the tolerance limit set The tolerance is s
51. t time moment Changing the parameters or enabling disabling it any other time will not affect anything e The Autoguiding works in a special mode when a displacement is in progress It starts to autoguide to the new position automatically with the current parameters but the guiding is stopped right after both of the correction signals axes got inactive at least for a moment since the start of the movement The new star position that is not the exact calculated position is then measured for max 2 seconds and the guiding is continued in that position and the Autoexposure is left to go on This method shorten the displacement time and gives more for imaging 18 5 Menu tree The menu is structurized around the function units From the main menu You can access these main functional units control screens besides other subscreens and menus Here is the menu structure except for the misc menu that will be detailed later at the screen descriptions Main menu Power off Autoexposure Guiding menu Random Displ Misc menu LiveView To navigate in the menu use SET and ESC buttons SET is to enter a subscreen while ESC is to exit the current one The previous screens and their selected items are stored in a stack by going back to them will hold the previous selection By entering a new one will have the default item selected on it To go to the main menu press ESC more times or keep it pressed autorepeat 19 5
52. the brightness of the selected star but forget it now this Firmware has a dispay bug here unfortunately To start following the selected star press SET button See Then You can monitor the star on the Guiding screen 5 1 9 where this action jumps Note the smaller rectangle is for live viewing of the selected star s CCD part currently not used always empty If the search was inefficient this is shown You can start a new search with the same parameters by pressing the SET button New search or go back to the Star Search screen by pressing ESC and change the parameters See Other notes The automatic star search method uses a 32 pixel width window Stars having this huge image or defocused spots may not result in a hit point or more points close to eachother Double stars within this size are also identified as single stars 34 5 1 8 Live View screen The screen does that it s name suggests The entire CCD surface is monitored on the LCD in realtime so far as a two state display can there are on bright and off dark pixels on it The on pixels show that the given part of the CCD is brighter than a threshold value Each displayed pixel corresponds to a 10x10 pixel field on the CCD surface its brightness is derived from those The method of calculation the brightness is described later gain decimal 1 9 profile The same variable as the image gain at the Star Search scr
53. the current calibration data if there is one The Calibration inverted text on the top indicates this screen If there is no calibration data present no data text is shown see screenshot at right and only one option is possible starting a new calibration with the Calibrate button The calibration procedure is the following First the DEC axis is moved according to the settings given in guider settings screen AG speed DEC value This helps the calibration to move the desired amount without a knowledge If the star moved a little no backlash is on the DEC now the measurement of the DEC direction and correction speed is started After it the RA axis direction and speed can be measured now easier the device supposes that the actual RA speed is equal or less than the DEC s Less due to the actual DEC coordinate where the mount points to After all is finished both the directions and speeds are stored as the calibration data The correction speeds precision can t be checked diretly but the directions can In an ideal case these directions vectors are orthogonal to eachother but during the measurement the star may drift some due to polar alignment failure or due to the periodic error of the RA axis The constant speed drifts are mostly corrected by the measurement method After the calibration the orthogonlity measure is displayed on the screen as ortho in percent The interpretation of the resulting val
54. to set it as the selected item if You go back with ESC 3 2 2 Variables parameters There are many types of items on the screens If an item holds a value its called variable or parameter Their value can be changed in editing mode For demonstration there are some examples Example A variable item is selected on the screen By pressing SET You can enter editing mode if it is allowed to be changed The SET bracket around the edited item indicates Beginning of editing the editing mode In this mode there is always a cursor that Sr Ss selects one digit and is shown inverse To move the cursor on the digits LEFT and gt LEFT RIGHT buttons can be used Moving the cursor use UP and DOWN buttons Use Sr Ss autorepeat of the buttons for faster gt UP changing of the digit value more times Increasing a digit To store the new value press SET again The new value immediately takes place in most of the cases Doing so we also gt SET leave the editing mode Storing the new value To change the value of the selected digit 12 To discard the new value edited to hold the old one press ESC This exits editing mode ESC Discarding the new value The editing process is always done on a temporary variable so it does not affect anything if You start an editing and then exit from it with ESC During editing the device uses the old original variable value Types of the items or parameters Decimal
55. typically constant for a well tested system e image gain decimal 1 9 profile The analog gain value of the CCD s signal See the table at 1 3 2 e expo time decimal 50 4000 ms profile The exposure time for the star search and later for the guiding in milliseconds The maximum is 4 seconds there is no reason to increase this limit e New search button Starts a new star search with the given parameters If the Camera is not working it is started taking some seconds then the exposure time plus about 2 5 seconds for the search procedure elapses Searching stars text is displayed meanwhile e Last results button Shows the last search s results again goes to the search result screen which appears after each new search Hold valid information until some other Camera function was not used The search result screen appears after a star serach which can be seen at right The top left big rectangle shows the entire CCD area Every active point pixel on it represents a found star these are the hits At top right is the index of the currently selected hit and the number of them The first 16 are memorized and shown only To select the next or previous hit press UP or DOWN buttons The selected one is displayed with a tiny rectangle see on screenshot The index orders the found stars nearly by their brightness The first index must be the brightest star found At bottom left there should be information about
56. ue is described later AQ The calibration procedure can be interrupted by pressing ESC The mount will stay in the position where it was stopped The mount is tries to set back to its original position only after all the calibration steps has run If a calibration has run with no error a calibration data is present The data consists of the directions on the CCD s surface of the two axes RA and DEC and their actual correction speeds This is displayed on the screen as on the screeenshot at right The two directions are shown in the guiding window that is now used for displaying only these vectors Both are normalized to equal length displayed Note that these may seem not orthogonal to eachother due to the CCD s and LCD s pixel aspect ratios but it shows the real moving directions when the guiding star is being monitored RA and DEC s correction speeds are shown at top right in pixels per second unit px s The next row shows the orthogonality measure of the two axes vectors This is calculated as follows RA RA and DEC vectors are normalized to unit DEC length Ther error e is the scalar multiply of these vectors e RA DEC cos a e The precision of the measurement the orthogonality O is o 1 e 100 The o value is displayed on the screen as Ortho in percent If this is 100 the orthogonality of the two direction vectors is perfect The value
57. ut 3 2 Main conception of the User Interface The display and controlling of the device is menu based By default there is always an active screen holding one selected item on it for most of the screens The selected item is always shown inverse This is something like a cursor for the actual screen items The selected item can be activated by pressing the SET button Activating means entering to editing mode to change its value or doing some function By default You can change the selected item move the cursor with UP and DOWN buttons and in some cases LEFT and RIGHT could also be used This screenshot below shows the main menu with the Exposure item selected on it 1ll Certain items behave differently There are number time and text types etc Text type items can lead to a submenu or are to do some function like a button while other number or time types store a value that could be edited changed and are called parameters or variables These are to setup parametrize the device to control its behaviour For details of the method of changing the parameters see 3 2 2 3 2 1 Menus The HC has a fixed menu tree structure From the main menu every submenu is accessible with a subscreen at the end that is for some specific function If an item leads to an other sub screen it is called menu item Exiting from a screen is done with ESC button When entering into a subscreen the selected item is memorized
58. veView screen 5 1 8 From main menu Guiding Live View With changing the imaging parameters find a star in the field of view the brightest possible but above magnitude of 4 might be way too bright Check with slightly pushing the tube that the seen spot is a real star and is not a hot pixel structure the star must move by the puhsing Choose one of the stars and You get to the Guiding screen 5 1 9 As an alternative You can use the automatic star search function also 5 1 7 that may take more time but is more comfortable and immune to single hot pixels gt On the 1 page of the Guiding screen 5 1 9 1 You can optimize the imaging parameters gain and exposure time This can be done the following way o Set the display mode to max Y o Change the parameters so that the star covers the full dynamic range the profile of the star reaches the bottom of the window it s not a problem if the bottom is only near to it or sometimes it saturates in some columns Take care of the followings the exposure time should be as much as possible as many as Your mount s periodic error s rate allows and as much as it smoothes the seeing enough not to chase that the gain should be as low as possible for the lowest readout noise An automatic procedure will be included soon to do this without human interaction gt Change to page 2 5 1 9 2 Delete the previous calibration if any and start a new one Re run the calibr
59. y of this type of items Can be a so called switch that can be altered by the SET button This is a two state parameter item For example enabling functions or modes are controlled by this type of items Commonly a character indicates the OFF and a e char the ON state Can be a special parameter that can have a few number of fix values displayed as a text For example on Live View screen this item can have only the max and avg values The value of most of the parameters or variables are stored into EEPROM memory of the HC at power off At the next power on they are initialized from here 3 2 3 Profiles Profile means the value of a set of variables parameters these are called profile variables The value of these can be set in each profile independently Changing the active profile will change the value of all these profile variables There are 3 separate profiles number 0 1 and 2 The active profile can be changed in the misc menu screen If doing so the old profile setting is stored into memory and the new one is loaded into the profile variables The change of these takes effect immediately and so there may be a question to stop the current autoguiding because all the guiding parameters are profile variables A profile can be interpreted as a trimmed set of parameters for each guiding solutions for example profile 0 for a guiding telescope profile 1 for off axis system and so on N

LACERTA M-GEN Stand-Alone AutoGuider - Pierro

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