Moravian Instruments G2-0402 User manual

G2 CCD
Camera
User's Guide

Version 3.1
Modified on March 11th, 2016
All information furnished by Moravian Instruments is believed to be accurate.
Moravian Instruments reserves the right to change any information contained
herein ithout notice.
G2 CCD devices are not authorized for and should not be used ithin Life
Support Systems ithout the specific ritten consent of the Moravian
Instruments. Product arranty is limited to repair or replacement of defective
components and does not cover injury or property or other consequential
damages.
Copyright © 2000-2016, Moravian Instruments
Moravian Instruments
Masarykova 1148
763 02 Zlín
Czech Republic
tel./fax: [phone]
: http:// .gxccd.com/
e-mail: [email protected]

Table of Contents
Introduction....................................................................................................4
G2 Camera Overvie .....................................................................................6
CCD and Camera Electronics.........................................................................9
CCD Chip...............................................................................................12
Model G2-0402.................................................................................13
Model G2-1600.................................................................................13
Model G2-3200.................................................................................14
Model G2-8300.................................................................................14
Model G2-2000.................................................................................14
Model G2-4000.................................................................................15
Camera Electronics.................................................................................15
Model G2-0402.................................................................................16
Model G2-1600.................................................................................16
Model G2-3200.................................................................................17
Model G2-8300.................................................................................17
Model G2-2000.................................................................................17
Model G2-4000.................................................................................17
CCD Cooling and Po er Supply..................................................................18
Po er Supply..........................................................................................18
Mechanical Specifications............................................................................21
Telescope adapters..................................................................................23
Camera Maintenance....................................................................................26
Desiccant exchange................................................................................26
Changing the silica-gel......................................................................27
Changing Filters......................................................................................29
Opening the camera head..................................................................29
Changing the Whole Filter Wheel..........................................................31
Changing the Telescope Adapter............................................................31
Po er Supply Fuse.................................................................................31
G2 Camera Revisions...................................................................................32
Revision 1...............................................................................................32
Revision 2...............................................................................................32
Revision 3...............................................................................................33
Revision 4...............................................................................................34

Introduction
Thank you for choosing the G2 CCD camera. The cooled, slo -scan series of
G2 cameras ere developed for imaging under extremely lo -light conditions
in astronomy, microscopy and similar areas. The development team focused to
every detail of camera mechanics, cooling, electronics and soft are to create
state-of-the-art product. G2 cameras feature compact and robust construction,
rich features, sophisticated soft are support and easy operation.
G2 cameras can contain filter heel ith 5 positions for 1.25“ filters. Camera
variants ithout internal filter heel can control external filter heel ith 12
positions for the same filter s or ith 10 positions for D36 mm filters.
Please note the G2 cameras are designed to ork in cooperation ith a host
Personal Computer (PC). As opposite to digital still cameras, hich are
operated independently on the computer, the scientific slo -scan, cooled
cameras usually require computer for operation control, image do nload,
processing and storage etc. To operate the G2 camera, you need a computer
hich:
1. Is compatible ith a PC standard.
2. Runs a modern 32-bit or 64-bit Windo s operating system.
Drivers for 32-bit and 64-bit Linux systems are also provided, but
camera control and image processing soft are, supplied ith the
camera, requires Windo s operating system.
3. Provides at last one free USB port.
The current series of G2 CCD cameras are designed to operate ith
USB 2.0 high-speed (480 Mbps) hosts. Although they are fully
back ard compatible ith USB 1.1 full-speed (12 Mbps) hosts, image
do nload time can be some hat longer if USB 1.1 connection is used.
A simple and cheap device called USB hub can expand number of
available USB port. Typical USB hub occupies one computer USB
port and offers four free ports. Make sure the USB hub is USB 2.0
high-speed compatible.
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But keep on mind that if more USB devices connected to one hub need
to communicate ith a host PC, USB hub shares its single up link line
to the host PC. Although G2 CCD cameras can operate through a USB
hub, it can negatively affect the camera performance, like do nload
time etc. It is recommended to connect other USB devices through
USB hub (e.g. the mouse) and to provide the camera a direct USB
connection to the host PC.
4. Alternatively it is possible to use the Gx Camera Ethernet Adapter.
This device can connect up to four Gx cameras of any type (not only
G3 and G4, but also G0, G1 and G2) and offers 1 Gbps and
10/100 Mbps Ethernet interface for direct connection to the host PC.
Because the PC then uses TCP/IP protocol to communicate ith the
cameras, it is possible to insert e.g. WiFi bridge or other net orking
device to the communication path.
The G2 CCD camera needs an external po er supply to operate. It is not
possible to run the camera from the po er lines provided by the USB cable,
hich is common for ebcams or very simple imagers. G2 CCD cameras
integrate highly efficient CCD chip cooling, shutter and filter heel, so their
po er requirements significantly exceed USB line po er capabilities. On the
other side separate po er source eliminates problems ith voltage drop on long
USB cables or ith dra ing of laptop batteries etc.
Also note the camera must be connected to some optical system (e.g. the
telescope) to capture images. The camera is designed for long exposures,
necessary to acquire the light from faint objects. If you plan to use the camera
ith the telescope, make sure the hole telescope/mount setup is capable to
track the target object smoothly during the exposure.
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G2 Camera Overview
G2 camera head is designed to be easily used ith a set of accessories to fulfill
various observing needs. Camera head itself is manufactured in t o different
variants:
●Camera ith internal filter heel.
●Camera ith control port for external filter heel. This model allo s
attachment of several variants of external filter heels ith various
number of filter positions and sizes.
Illustration 1: G2 camera without filter wheel (left), with internal filter wheel (middle)
and with attached external filter wheel (right).
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Illustration 2: Schematic diagram of G2 camera system components
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Components of G2 Camera system include:
1. G2 camera head ith internal filter heel.
2. G2 camera head ithout internal filter heel, ready for attaching of
external filter heel.
3. G0 Guider camera.
4. G1 Guider camera.
G0 and G1 cameras are completely independent devices ith their
o n USB connection to the host PC. They can be used on G2 OAG,
on standalone guiding telescope or for any other imaging purpose, like
Moon or planetary imaging etc.
Both G0 and G1 camera can share the Gx Camera Ethernet Adapter
ith up to 3 other Gx cameras to be accessed over net ork.
5. External filter heel.
6. Off-axis guider adapter, optionally ith M42×0.75 thread (T-thread)
or M48×0.75 thread.
7. Thin spacer. Camera ith internal filter heel and this spacer has the
same back focal distance as camera ith external filter heel.
8. Thick spacer. Camera ithout internal filter heel and this spacer has
the same back focal distance as camera ith external filter heel.
9. Nikon bayonet adapter for Nikon compatible lenses.
10. Canon EOS bayonet adapter for Canon compatible lenses.
11. T-thread (M42×0.75) adapter.
12. 2-inch barrel adapter.
Other available adapters are missing from this illustration, e.g.
M48×0.75 thread adapter, M42×1 Pentax/Parktica lens adapter etc.
13. Gx Camera Ethernet Adapter allo s connection of up to 4 Gx cameras
of any type on the one side and 1 Gbps Ethernet on the other side. This
adapter allo s access to connected Gx cameras using routable TCP/IP
protocol over practically unlimited distance.
14. The hole system is controlled from a host PC.
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CCD and Camera Electronics
G2 series of CCD cameras are manufactured ith t o kinds of CCD detectors:
●G2 cameras with Kodak KAF Full Frame (FF) CCD architecture.
Almost all Full Frame CCD detector area is exposed to light. This is
hy these detectors provide very high quantum efficiency. FF CCD
detectors, intended for research applications, are not equipped ith so-
called Anti Blooming Gate (ABG – a gate, hich prohibits blooming
of the charge to neighboring pixels hen image is over-exposed) to
ensure linear response to light through the hole dynamic range. FF
CCD detectors used for astrophotography are equipped ith ABG to
eliminate disrupting blooming streaks ithin field of vie .
Cameras ith Full Frame, non-ABG detectors are suitable for
scientific applications, here linear response is necessary for
photometric applications in astronomy, microscopy etc. High quantum
efficiency could be used also for narro -band imaging, here
overexposure is a rare exception, and for imaging of small objects
ithout a bright star in the field of vie .
Illustration : “Full Frame” CCD schematic diagram

●G2 cameras with Kodak KAI Interline Transfer (IT) architecture.
There is a shielded column of pixels just beside each column of active
pixels on these detectors. The shielded columns are called Vertical
registers. One pulse moves charge from exposed pixels to shielded
pixels on the end of each exposure. The the charge is moved from
vertical registers to horizontal register and digitized in the same ay
like in the case of Full Frame detectors. This mechanism is also kno n
as “electronic shuttering”, because it allo s very short exposures and
also digitization of the image ithout mechanically shielding of the
detector from incoming light.
Also G2 cameras ith IT CCDs are equipped ith mechanical shutter,
because electronic shutter does not allo dark-frame exposures,
necessary for proper image calibration etc.
The price for electronic shutter if lo er quantum efficiency
(sensitivity) of IT detectors compared to FF ones. Also all IT detectors
are equipped ith ABG, so they can acquire images of very bright
objects ithout charge blooming to neighboring pixels.
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Illustration 4: “Interline Transfer” CCD schematic diagram

G2 camera models ith Full Frame CCD detectors:
Model G2-0402 G2-1600 G2-3200 G2-8300
CCD chip KAF-0402ME KAF-1603ME KAF-3200ME KAF-8300
Resolution 768×512 1536×1024 2184×1472 3358×2536
Pixel size 9×9 µm 9×9 µm 6.8×6.8 µm 5,4×5,4 µm
CCD area 6.9×4.6 mm 13.8×9.2 mm 14.9×10.0 mm 18,1×13,7 mm
ABG No No No Yes
Color mask No No No No (see Note)
G2-8300 camera is available in the G2-8300C version ith color CCD detector
( ith Bayer mask), capable of single-shot color images.
G2 camera models ith Interline Transfer CCD detectors::
Model G2-2000 G2-2000C G2-4000 G2-4000C
CCD chip KAI-2020 KAI-2020 KAI-4022 KAI-4022
Resolution 1604×1204 1604×1204 2056×2062 2056×2062
Pixel size 7,4×7,4 µm 7,4×7,4 µm 7,4×7,4 µm 7,4×7,4 µm
CCD area 11,8×9,0 mm 11,8×9,0 mm 15,2×15,2 mm 15,2×15,2 mm
ABG Yes Yes Yes Yes
Color mask No Yes No Yes
Cameras ith “C” suffix contains CCD detector covered ith so-called Bayer
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mask. Color filters of three basic colors (red, green, blue) cover all pixels, so
every pixels detects only light of particular color.
These cameras are able to acquire color image in single exposure, ithout the
necessity to change color filters. On the other side color mask brings lo er
sensitivity and limits the capability to perform exposures using narro -band
filters etc.
Because each pixel is covered by one of three basic color filters, it is necessary
to compute (interpolate) remaining t o colors for each pixel, hich of course
limits resolution of color image. Imaging using color detectors is described in
the “Color images” chapter.
CCD Chip
Quantum efficiency (sensitivity) of CCD detectors used in G2 cameras depends
on the particular camera model.
Inherent dark current of these detectors is quite lo compared to other CCD
detectors, suitable for scientific applications, hich results into very good
signal/noise ratio.
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Illustration 5: Quantum efficiency of Kodak CCD detectors used in G2 cameras

Model G2-0 02
G2-0402 model uses 0.4 MPx Kodak KAF-0402ME.
Resolution 768×512 pixels
Pixel size 9×9 µm
Imaging area 6.9×4.6 mm
Full well capacity Approx. 100 000 e-
Output node capacity Approx. 220 000 e-
Dark current 1 e-/s/pixel at 0°C
Dark signal doubling 6.3 °C
Model G2-1600
G2-1600 model uses 1.6 MPx Kodak KAF-1603ME.
Resolution 1536×1024 pixels
Pixel size 9×9 µm
Imaging area 13.8×9.2 mm
Full well capacity Approx. 100 000 e-
Output node capacity Approx. 220 000 e-
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Illustration 6: Dark current of Kodak CCD detectors, used in G2 cameras

Dark current 1 e-/s/pixel at 0°C
Dark signal doubling 6.3 °C
Model G2-3200
G2-3200 model uses 3.2 MPx Kodak KAF-3200ME.
Resolution 2184×1472 pixels
Pixel size 6.8×6.8 µm
Imaging area 14.9×10.0 mm
Full well capacity Approx. 55 000 e-
Output node capacity Approx. 110 000 e-
Dark current 0.8 e-/s/pixel at 0°C
Dark signal doubling 6 °C
Model G2-8300
G2-8300 model uses 8 MPx Kodak KAF-8300.
Resolution 3358×2536 pixels
Pixel size 5,4×5,4 µm
Imaging area 18,1×13,7 mm
Full well capacity Approx. 25 000 e-
Output node capacity Approx. 55 000 e-
Dark current 0.15 e-/s/pixel at 0°C
Dark signal doubling 5.8 °C
KAF-8300 CCD detector ith color (Bayer) mask can be used in the G2-8300C
camera.
Model G2-2000
G2-2000 uses 2 MPx CCD Kodak KAI-2020.
Resolution 1604×1204 pixels
Pixel size 7.4×7.4 µm
Imaging area 11.9×8.9 mm
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Full well capacity Approx. 40 000 e-
Output node capacity Approx. 80 000 e-
Dark current 0.3 e-/s/pixel at 0°C
Dark signal doubling 7 °C
KAI-2020 CCD detector ith color (Bayer) mask can be used in the G2-2000C
camera.
Model G2- 000
G2-2000 uses 4 MPx CCD Kodak KAI-4022.
Resolution 2056×2062 pixels
Pixel size 7.4×7.4 µm
Imaging area 15.2×15.2 mm
Full well capacity Approx. 40 000 e-
Output node capacity Approx. 80 000 e-
Dark current 0.3 e-/s/pixel at 0°C
Dark signal doubling 7 °C
KAI-4022 CCD detector ith color (Bayer) mask can be used in the G2-4000C
camera.
Camera Electronics
Remark
Stated values are valid for G2 cameras revision 4. Previous revisions could
differ in some parameters. Refer to chapter “G2 Camera Revisions” for
differences among individual revisions.
Some parameters (e.g. camera gain) are defined by the used system driver, so
they depend on the version of actually used driver. If the Gx Camera Ethernet
Adapter is used, system driver is defined by the firm are version of the
Ethernet Adapter device.
16-bit A/D converter ith correlated double sampling ensures high dynamic
range and CCD chip-limited readout noise. Fast USB interface ensures image
do nload time ithin seconds.
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ADC resolution 16 bits
Sampling method Correlated double sampling
Read modes Previe
Lo -noise
Horizontal binning 1 to 4 pixels
Vertical binning 1 to 4 pixels
Sub-frame readout Arbitrary sub-frame
Computer interface USB 2.0 high-speed
USB 1.1 full-speed compatible
Binning can be combined independently on both axes.
Image do nload time and system read noise depends on the CCD chip used in
particular camera model.
Model G2-0 02
Gain 1.5e-/ADU (1×1 binning)
2.0e-/ADU (other binnings)
System read noise 15 e- (Lo Noise mode)
17 e- (Previe mode)
Full frame download 0.7 s (Lo Noise mode)
0.5 s (Previe mode)
Model G2-1600
Gain 1.5e-/ADU (1×1 binning)
2.0e-/ADU (other binnings)
System read noise 15 e- (Lo Noise mode)
17 e- (Previe mode)
Full frame download 2.6 s (Lo Noise mode)
1.8 s (Previe mode)
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Model G2-3200
Gain 0.8 e-/ADU (1×1 binning)
1.3 e-/ADU (other binnings)
System read noise 7 e- (Lo Noise mode)
10 e- (Previe mode)
Full frame download 5.5 s (Lo Noise mode)
3.8 s (Previe mode)
Model G2-8300
Gain 0.4 e-/ADU (1×1 binning)
0.8 e-/ADU (other binnings)
System read noise 8 e- (Lo Noise mode)
9 e- ( Previe mode)
Full frame download 14.2 s (Lo Noise mode)
9.8 s (Previe mode)
Model G2-2000
Gain 0.4 e-/ADU (1×1 binning)
0.8 e-/ADU (other binnings)
System read noise 7 e- (Lo Noise mode)
9 e- ( Previe mode)
Full frame download 3.1 s (Lo Noise mode)
2.1 s ( Previe mode)
Model G2- 000
Gain 0.4 e-/ADU (1×1 binning)
0.8 e-/ADU (other binnings)
System read noise 7 e- (Lo Noise mode)
9 e- (Previe mode)
Full frame download 6.7 s (Lo Noise mode)
4.5 s (Previe mode)
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CCD Cooling and Power Supply
Regulated t o-stage thermo-electric cooling is capable to cool the CCD chip up
to 50 °C belo ambient temperature. The Peltier hot side is cooled by a fan.
The CCD chip temperature is regulated ith ±0.1 °C precision. High
temperature drop and precision regulation ensure very lo dark current for long
exposures and allo image proper calibration.
The camera head contains t o temperature sensors – the first sensor measures
directly the temperature of the CCD chip. The second one measures the
temperature of the air cooling the Peltier hot side.
The cooling performance depends on the environmental conditions and also on
the po er supply. If the po er supply voltage drops belo 12 V, the maximum
temperature drop is lo er.
CCD chip cooling Thermoelectric (Peltier modules)
TEC modules T o stages
Maximal ∆T>50 °C belo ambient
Regulated ∆T48 °C belo ambient (85% cooling)
Regulation precision ±0.1 °C
Hot side cooling Forced air cooling (fan)
Optional heat exchanger for liquid coolant
Maximum temperature difference bet een CCD and ambient air may exceed
50 °C hen the cooling runs at 100% po er. Ho ever, temperature cannot be
regulated in such case, camera has no room for lo ering the CCD temperature
hen the ambient temperature rises. The 45 °C temperature drop can be
achieved ith cooling running at approx. 85% po er, hich provides enough
room for regulation.
Power Supply
The 12 V DC po er supply enables camera operation from arbitrary po er
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source including batteries, all adapters etc. Universal 100-240 V AC/50-
60 Hz, 60 W “brick” adapter is supplied ith the camera. Although the camera
po er consumption does not exceed 30 W, the 60 W po er supply ensures
noise-free operation.
Camera head supply 12 V DC
Camera head power consumption 30 W
Adapter input voltage 100-240 V AC/50-60 Hz
Adapter output voltage 12 V DC/5 A
Adapter maximum power 60 W
Po er consumption is measured on the AC side of the supplied 12 V AC/DC
po er supply. Camera consumes less energy from 12 V po er supply than
state here.
The camera contains its o n po er supplies inside, so it can be po ered by
unregulated 12 V DC po er source – the input voltage can be any here
bet een 10 and 14 V. Ho ever, some parameters (like cooling efficiency) can
degrade if the supply drops belo 12 V.
G2 CCD camera measures its input voltage and provides it to the control
soft are. Input voltage is displayed in the Cooling tab of the CCD Camera
control tool in the SIPS. This feature is important especially if you po er the
camera from batteries.
Illustration 7: 12 V DC/5 A power supply adapter for
G2 CCD Camera
1

Warning:
The po er connector on the camera head uses center-plus pin. Although all
modern po er supplies use this configuration, al ays make sure the polarity is
correct if you use o n po er source.
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