Lacerta M-GEN User manual

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LACERTA M-GEN
Stand-Alone AutoGuider
User’s manual for Firmware 02.50
Created by Zoltán Tobler
Last updated: 27 November 2017
Table of contents
1 ABOUT THE HARDWARE..............................................................................................................................2
1.1 PARTS OF THE DEVICE ....................................................................................................................................2
1.2 POWERING THE DEVICE ..................................................................................................................................4
1.3 ELECTRICAL CHARACTERISTICS .....................................................................................................................5
1.3.1 Specification of the HC and Camera .....................................................................................................5
1.3.2 Imaging specification of the Camera.....................................................................................................6
1.4 TURNING ON AND OFF THE DEVICE.................................................................................................................7
1.5 UPDATE MODE.............................................................................................................................................8
1.6 HARDWARE TYPES..........................................................................................................................................8
2 NEW FEATURES IN FW. 02.50.......................................................................................................................9
2.1 PREVIOUS VERSION CHANGES.........................................................................................................................9
3 ABOUT THE USER INTERFACE.................................................................................................................11
3.1 BUTTONS AND LEDS....................................................................................................................................11
3.2 MAIN CONCEPTION OF THE USER INTERFACE...............................................................................................11
3.2.1 Menus ..................................................................................................................................................12
3.2.2 Variables (parameters)........................................................................................................................12
3.2.3 Profiles ................................................................................................................................................14
4 PARTS OF THE SOFTWARE, FUNCTIONAL UNITS..............................................................................15
4.1 AUTOGUIDING FUNCTION (AG) ...................................................................................................................15
4.2 AUTOEXPOSURE FUNCTION (AE).................................................................................................................16
4.3 RANDOM DISPLACEMENT (DITHERING)FUNCTION (RD) ..............................................................................16
4.4 FILESYSTEM (FS) .........................................................................................................................................17
4.4.1 When is the file written? ......................................................................................................................17
4.5 COOPERATION OF THE FUNCTIONAL UNITS...................................................................................................19
5 MENU TREE.....................................................................................................................................................20
5.1 SCREENS AND FUNCTIONS DETAILED............................................................................................................21
5.1.1 AutoExposure (AE) screen...................................................................................................................22
5.1.2 AutoExposure program list screen ......................................................................................................24
5.1.3 Random Displacement (RD) screen.....................................................................................................27
5.1.4 Misc. screen.........................................................................................................................................29
5.1.5 Power off screen..................................................................................................................................35
5.1.6 Guiding menu screen...........................................................................................................................36
5.1.7 Guider setup screen.............................................................................................................................37
5.1.8 Star Search screen...............................................................................................................................38
5.1.9 Live View screen..................................................................................................................................40
5.1.10 Guiding screen...................................................................................................................................42
6 MORE DETAILED ABOUT... ........................................................................................................................54
6.1 ... CCD BINNING...........................................................................................................................................54
6.2 ... THE NEW IMAGE PROCESSING METHOD ...................................................................................................55

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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:
Handcontroller (referenced as HC). It 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.
Note that there is a protector film on the display window, You must remove it
before the first use! This is quite invisible in dark when the LCD backlight is on,
some can let it on to protect the window from scratching and remove only if too
much scratch is visible yet.
The connetor panel is located at the bottom of the HC box:
These are the following from left to right:

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oCanon EOS compatible shutter output (3.5mm stereo jack conn.)
oCamera port (RJ-45 type female conn., can be used any (max. 2m) UTP
cable too but the supplied cable is preferred. Note: NEVER try to use a UTP
cross cable!)
oDC power input (5.5/2.1mm size) (12V nominal, 9-15V), tip positive
(polarity-protected)
oST-4 compatible autoguider output (RJ-12 type female conn.)
oPC communication port (USB-B mini 5-pin conn.)
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 4-5mm 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 CCD 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.
(The CCD part number is ICX279AL-E.)
Note: ont the CCD there is the protector film by default. You must remove
it before the first use! Cleaning the CCD’s glass is done as for any other
optical surfaces. Avoid scratching! 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.)
Supplied cables (this may vary):

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o1 piece of Camera cable, similar to a straight UTP cable. Used to connect
the Camera with the Handcontroller. It’s length is around 1.8-2m.
o1 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.
o1 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 3.5mm stereo
jack ending, 2m length. (Can be used directly for Canon EOS 550D for
example.))
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 (peak voltage max. 18V)! The output power of the DC supply
must be minimum 2W (at 12V) but the supply may source higher currents than 160mA for a
short time (about 0.1s).
Be careful choosing the type of the DC power source, it MUST BE well stabilized or a
constant source. A battery, stabilized DC or switching regulator should be used! An
unfiltered, only AC-rectified power (which has a heavy transformer in it) may not supply the
device properly, this could lead to sudden reset/turn-off of the device or even damage the
input circuitry! (For example a 220V-input and 12V / 800mA-output rectified power supply
could easily source over 20V peak voltage at low load, which is harmful for the device!)
“Logic only” mode: (USB connection: Firmware update etc.)
If the Camera is not connected or will not be used for imaging the USB bus can also
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.
NOTE: new type devices (boot version ≥$14) may fail to update the Camera’s firmware
if the USB voltage is well lower than 5V. In this case, power the device also from its DC
input!
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.

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1.3 Electrical characteristics
1.3.1 Specification of the HC and Camera
Values for HC with BOOT version $14 or above.
Note: All DC input current values are for a nominal 12V input. These currents
change with the input voltage.
Min.
Typical
Max.
unit
Notes
DC power supply
9
12
15
V
7
Active input current (no light)
(full light)
96
160
mA
1,3,4,5
109
160
mA
1,3,4,5
HC only input current (no light)
(full light)
27
mA
1
33
mA
1
Power-down mode with USB
w/o USB
10
mA
6
mA
ST-4 out. pull-down current
5.3
mA
6
Shutter out. pull-down current
1.1
mA
6
1 with connection to PC via USB
3 ‘active’ means an active Camera (autoguiding or LiveView)
4 the value changes as some parameters do (gain, exp.time)
5 there is a fuse in the HC
6 for a TTL low input level (below 0.8V @ 5V)
7 the peak input voltage MUST NOT exceed 20V!
Values for HC with BOOT version $13 or below
Min.
Typical
Max.
unit
Notes
DC power supply
9
12
15
V
7
Active input current
110-116
200
mA
1,2,3,4,5
HC only input current
27
mA
1,2
Power-down current with USB
without USB
9
mA
6
mA
RED display backlight
0
30
mA
AMBER display backlight
0
7
mA
ST-4 out. pull-down current
1.1
mA
Shutter out. pull-down current
0.5
mA
1 with connection to PC via USB
2 older devices may draw about 8mA more current due to the MCU
(see the table above for the other notes)
Note.: values shown gray are only informational and derived from the
design.

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1.3.2 Imaging specification of the Camera
ADU means: Analog to Digital conversion Unit (= a digital step)
e-means: electron
RMS means: standard deviation (statistical); Root Mean Square
Min.
Typical
Max.
unit
Notes
CCD active pixel area
752 × 582
pixel
3.65 × 2.7
mm
CCD pixel size
4.85 × 4.65
μm
Imaging depth
8
bit
Image conversion speed
2M
pixel/sec
max.
Conversion (min. gain (2))
(max. gain (9))
44
e-/ADU
1
1.75
e-/ADU
1
Readout noise at min. gain (2)
22
e- (RMS)
1
Readout noise at max. gain (9)
5.9
7.1
8.5
e- (RMS)
1,2,4
Average dark current
3.2
e-/px/sec
1,2
Pixel capacity
10k
e-
1
Operating temperature
-10
60
°C
3
1 the value is only informative but measured on some instances
2 at 23ºC CCD temperature
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 limits 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 full scale (from 2 to 9) cover 3.5 magnitudes
(×25). The table below shows the physical imaging parameters for each gain value
(approximately):
gain
conversion
(e-/ADU)
pixel saturation
(e-)
1
70.0
16700
2
44.0
10500
3
25.7
6650
4
17.5
4200
5
11.0
2650
6
7.0
1670
7
4.4
1050
8
2.77
665
9
1.75
420
Note: gain 1 is not available from FW v2.00 due to
possible early pixel-saturation

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1.4 Turning 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 (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 (1.5). 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
firmware (using PC application).
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.
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 cable 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).

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1.5 UPDATE mode
Also known as BOOT mode. The device always starts in BOOT mode by pressing ESC,
but doesn’t start the firmware if You hold ESC button for more than 1 second. If there is no
valid firmware on the device, UPDATE mode will start anyway with the text ‘NO
FIRMWARE’.
This mode is used to update the Firmware or download/refresh stored parameter data. The
PC application may make the running Firmware to enter this mode (even during autoguiding),
but from Fw. 2.20 it is allowed to do so, the open file will be closed and parameters get
stored.
1.6 Hardware types
There are two types of hardware of this device (HandController and Camera). The newer
will show a little X right to the ‘UPDATE MODE’ text to indicate the new hardware type.
Besides the HC will show a BOOT version of $14 or above and the Camera BOOT version of
$14 or above as well. (See PC app.’s manual how to check this.) Lower BOOT versions
indicate ‘old’ hardware.
Note that the new hardware can not run Firmware version older than 2.00 due to the
hardware change. Uploading such an old firmware will succeed but the HandController will
display ‘WRONG FIRMWARE’ in update mode.
The difference between the two hardvare types are the following:
the new can be turned on by remote (USB) while the old can not;
the new can be used with a (supplied) 6-wire cable while the old works only with a
8-wire one;
the new can’t run a Firmware below 2.00;
Types of the supplied camera-cables:
8-wire black “telephone” (flat) cable with black connector (Cbb)
6-wire yellow silicone-covered cable with black connector (Cyb)
8-wire yellow silicone-covered cable with white connector (Cyw)
same as Cbb but producted after the year 2014 (Cbb2)
any straight UTP Cat5e cable (any color), < 3m (U)
The table below is important only if You want to use different HC and Camera (not from
the same device pack). The HC and Camera is advised to be used always from the same pack,
the following configurations would work only:
Cbb
■──■
Cyb
■──■
Cyw
□──□
Cbb2
■──■
U
■──■
old HC, old Cam.

─



new HC, new Cam.
()




old HC, new Cam.
()
()
()
()
()
new HC, old Cam.
X
─
X
X
X
─= not working
()= must be working but not guaranteed
X=not working. The devices may be damaged!

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2 New features in Fw. 02.50
oExclusive AG output mode has been extended with variable dead time and it is
applied between each AG signal change. (This is a workaround for some mounts
that can be stuck in one direction while AG signal ‘suddenly’ changes to the
opposite way.)
oA constant 0.2s AG signal idle time is inserted between RD movement and AE
exposure end. (This is the same workaround for some mounts that don’t need
exclusive AG out mode but still could be stuck at dithering.)
oFixed bugs in PC App:
CSV format selection (separator and decimal point mode) is fixed.
When calculating PE, day step (23:59 to 0:00) is handled well.
2.1 Previous version changes
From 02.42:
oA ‘factory reset’ possible from Fw., for all the variables in the device. (at Misc. /
Mode settings / …)
oSomewhat better star search results at high binning modes.
(An AutoExposure pause bug has been fixed in 2.41 release meanwhile.)
From 02.40:
oThe polar alignment feature is now available for mounts without DEC axis.
oOptional “focusing mask warning” feature for AutoExposure to avoid telescope
time to be wasted because of the forgotten (not removed) mask.
From 02.30:
oA precise polar aligment function/screen is available. The method is the
‘declination drift’ or ‘Schneier’ method.
From 02.21:
oFixed bug:
‘Disable direction’ type backlash compensation worked buggy.
From 02.20:

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oAutomatic shutdown (power-off) possible at a given time.
oDEC backlash “elimination” is possible. Two methods are offered.
oCalibration data can be restored after deletion, until a new calibration is done.
oFixed bugs:
Calibration: is more precise at high exposure time; fixed ‘random
characters written’on the screen for some rare error.
Exclusive AG out mode was wrong for the manual mode.
From 02.12:
oAstro Photography Tool is able to inform M-Gen about the externally controlled
exposure, so that M-Gen saves guiding positions to create guiding diagrams.
o(Mech./star) emulation mode is available. (It has been developed only for testing
indoor.) More on this at the switch’s description.
oAfter a calibration has failed / been stopped, the mount is restored to its starting
position (no backlash is assumed).
oFw. version show on main menu header; DC input voltage can be seen at guiding
screen page 5/5, inside “more..” item.
oFixed bug:
LiveView mode timed out if using at least 4x4 binning and more than ca. 3
seconds exposure.