Moravian instruments, Inc., source: https://www.gxccd.com/art?id=366&lang=409, printed: 02/11/2024 19:03:25

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G3-11000, G3-16200, G3-1000 and G3-6300 CCD Cameras
 Large format CCD cameras of the G3 series are designed for up to 24x36 mm (photographic “full-frame” format) CCD detectors. G3 series inherits from G2 cameras — camera handling, software control, power supply and connection to the host PC using fast USB interface is the same. Design of both series is very similar and although G3 camera head is naturally bigger, it contains all mechanics and electronics and offers only power and USB connectors. As like in the case of G2 cameras, G3 head contains mechanical shutter and integrated filter wheel for five 2-inch filters. Read noise is also limited only by CCD itself so G3 series surpasses competing products. Precisely regulated cooling achieves detector temperatures up to 50 °C below ambient temperature.

G3 cameras can contain OnSemi KAF Full-Frame CCD detectors as well as KAI Interline Transfer ones.

  • OnSemi KAF CCDs without ABG (Anti-Blooming Gate) offer linear response to light are suitable for scientific applications. Large area detectors with large pixels fit well to long focal length of professional observatory telescopes. Large pixels enhance image dynamic range.

  • OnSemi KAF CCDs with ABG can be used both for research applications and also for astrophotography. Anti-blooming ensures round shapes of bright stars, while the Full-Frame architecture provide clean and uniform frames without artifacts.

  • OnSemi KAI detectors with ABG and electronic shutter could be used for astrophotography. Anti-blooming ensures round shapes of bright stars, which cannot be avoided especially on wide field images.

No matter if your target is reliable scientific data or beautiful images of deep-sky objects, G3 cameras are able to provide both.

G3 Camera Overview

G3 camera head is designed to be easily used with a set of accessories to fulfill various observing needs. Camera head itself is manufactured in two different variants:

  • Camera with internal filter wheel for five 2" or D50 mm unmounted filters.

  • Camera with control port for external filter wheel. This model allows attachment of the external filter wheel for seven 2" or D50 mm unmounted filters.

Camera head and numerous accessories comprise imaging system, capable to be tailored for many applications.

  1. G3 camera head with internal filter wheel

  2. G3 camera head capable to control External Filter Wheel

  3. External Filter Wheel “S” size (7 positions)

  4. External Filter Wheel “L” size (9 or 7 positions)

  5. G0 Guider camera

  6. G1 Guider camera

  7. Off-Axis Guider with M68 × 1 thread

  8. Spacer compensating IFW and EFW back focal distance

  9. 1.75” dovetail rail for G3 camera head

  10. Gx Camera Ethernet Adapter (x86 CPU)

  11. Gx Camera Ethernet Adapter (ARM CPU)

    Remark:

    Camera Ethernet Adapter allows connection of up to 4 Gx cameras of any type on the one side and 1 Gbps Ethernet on the other side. This adapter allows access to connected Gx cameras using routable TCP/IP protocol over practically unlimited distance.

  12. 5-positions internal filter wheel for 2”/D50 mm filters

  13. 7-positions external filter wheel “S” for 2”/D50 mm filters

  14. 9-positions external filter wheel “L” for 2”/D50 mm filters

  15. 7-positions external filter wheel “L” for 50 × 50 mm filters

  16. 2-inch barrel adapter

  17. T-thread (M42 × 0.75) adapter

  18. Canon EOS bayonet adapter for Canon compatible lenses

  19. Nikon bayonet adapter for Nikon compatible lenses

G3 cameras are designed to work in cooperation with a host Personal Computer (PC). As opposite to digital still cameras, which are operated independently on the computer, the scientific slow-scan, cooled cameras usually require computer for operation control, image download, processing and storage etc. To operate G3 camera, you need a computer which:

  • Is compatible with a PC standard.

  • Runs a modern 32-bit or 64-bit Windows operating system.

    Remark:

    Drivers for 32-bit and 64-bit Linux systems are also provided, but camera control and image processing software, supplied with the camera, requires Windows operating system.

  • Provides at last one free USB port.

    Remark:

    The current series of G3 cameras are designed to operate with USB 2.0 high-speed (480 Mbps) hosts. Although they are fully backward compatible with USB 1.1 full-speed (12 Mbps) hosts, image download time can be somewhat longer if USB 1.1 connection is used.

  • 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, but also G0, G1, G2 and G4) 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 with the cameras, it is possible to insert e.g. WiFi bridge or other networking device to the communication path.

G3 Camera Models

G3 series contains the following camera models:

Model Color mask ABG CCD chip Resolution Pixel size Image area Download time
G3-01000 no no KAF-1001E 1024 × 1024 24 × 24 μm 24.6 × 24.6 mm ~ 1.3 s
G3-06300 no no KAF-6303E 3072 × 2048 9 × 9 μm 27.7 × 18.4 mm ~ 8 s
G3-16200 no 2800× KAF-16200 4524 × 3624 6 × 6 μm 27.2 × 21.8 mm ~ 19 s
G3-16200C RGBG (Bayer) 2800× KAF-16200 4524 × 3624 6 × 6 μm 27.2 × 21.8 mm ~ 19 s
G3-11000 no >1000× KAI-11002 4032 × 2688 9 × 9 μm 36.3 × 24.2 mm ~ 11 s
G3-11000C RGBG (Bayer) >1000× KAI-11002 4032 × 2688 9 × 9 μm 36.3 × 24.2 mm ~ 11 s

G3 CCD Cameras Technical Specifications

CCD chip

G3 CCD cameras use OnSemi KAF Full Frame CCD detectors or KAI Interline transfer CCD detectors with ABG and electronics shutter. Advanced manufacturing technologies like transparent electrodes and microlenses on the chip surface ensure high quantum efficiency. The inherent dark current of these detectors is very low compared to other scientific-grade CCDs, so the resulting image S/N ratio is very good.

CCD detector with 24 × 36 mm area used in G3-11000 camera

CCD detector with 24 × 36 mm area used in G3-11000 camera

Model G3-1000

G3-1000 model uses 1 MPx OnSemi KAF-1001E CCD.

Resolution 1024 (H) × 1024 (V) pixels
Pixel size 24 μm (H) × 24 μm (V)
Image area 24.6 mm (H) × 24.6 mm (V)
Full well capacity ~220,000 e-
Output node capacity ~650,000 e-
Dark current 17 e-/s/pixel at 0 °C
Dark signal doubling temperature 5.5 °C

KAF-1001E CCD specifications

KAF-1001E CCD and its quantum efficiency

Model G3-6300

G3-6300 model uses 6 MPx OnSemi KAF-6303E CCD.

Resolution 3072 (H) × 2048 (V) pixels
Pixel size 9 μm (H) × 9 μm (V)
Image area 27.6 mm (H) × 18.4 mm (V)
Full well capacity ~100,000 e-
Output node capacity ~220,000 e-
Dark current 1 e-/s/pixel at 0 °C
Dark signal doubling temperature 6.3 °C

KAF-6303E CCD specifications

KAF-6303E CCD and its quantum efficiency

Model G3-16200

G3-16200 uses 16 MPx OnSemi KAF-16200 CCD with APS-H format.

Resolution 4524 (H) × 3624 (V) pixels
Pixel size 6 μm (H) × 6 μm (V)
Image area 27.2 mm (H) × 21.8 mm (V)
Full well capacity ~41,000 e-
Dark current 0.08 e-/s/pixel at 0 °C
Dark signal doubling temperature 5.7 °C

KAF-16200 CCD

KAF-16200 CCD and its monochrome and color quantum efficiency

Model G3-11000

G3-11000 uses 11 MPx OnSemi KAI-11002 Class 1 or 2 CCD.

Resolution 4032 (H) × 2688 (V) pixels
Pixel size 9 μm (H) × 9 μm (V)
Image area 36.3 mm (H) × 24.2 mm (V)
Full well capacity ~60,000 e-
Dark current 12 e-/s/pixel at 0 °C
Dark signal doubling temperature 7 °C

KAI-11002 CCD

KAI-11002 CCD and its quantum efficiency

Camera Electronics

16-bit A/D converter with correlated double sampling ensures high dynamic range and CCD chip-limited readout noise. Fast USB interface ensures image download time within seconds.

Maximum length of single USB cable is 5 m. This length can be extended for instance to 10 m by using single USB hub or USB active extender cable. Up to 100 m extension can be achieved with third-party extender.

Gx Camera Ethernet Adapter device allows connection of up to four Gx cameras of any type through Ethernet interface and TCP/IP network. Because TCP/IP protocol can be routed, the distance between camera and host PC can be virtually unlimited.

ADC resolution 16 bits
Sampling method Correlated double sampling
Read modes Preview
  Low-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

Camera electronics specifications

Image download time depends on the CCD chip used in particular camera model. Also the read noise depends on the chip as well as on the read mode.

  • Standard read mode provides system read noise approx. 1 e- above CCD chip read noise.

  • LN (Low-noise) read mode is somewhat slower (approx. 1.2×), but ensures system read noise equal or smaller than the manufacturer-specified chip read noise.

Model G3-1000

Gain 3 e-/ADU (1 × 1 binning)
  5 e-/ADU (other binnings)
System read noise 12 e- RMS (LN read)
  15 e- RMS (standard read)
Full frame download 1.6 s (LN read)
  1.3 s (standard read)

G3-1000 electronics specification

Model G3-6300

Gain 1.5 e-/ADU (1 × 1 binning)
  2.3 e-/ADU (other binnings)
System read noise 10 e- RMS (LN read)
  12 e- RMS (standard read)
Full frame download 9.4 s (LN read)
  7.3 s (standard read)

G3-6300 electronics specification

Model G3-16200

Gain 0.6 e-/ADU (1 × 1 binning)
  1.0 e-/ADU (other binnings)
System read noise 10 e- RMS (LN read)
  11 e- RMS (standard read)
Full frame download 24.5 s (LN read)
  18.8 s (standard read)

G3-16200 electronics specification

Model G3-11000

Gain 0.8 e-/ADU (1 × 1 binning)
  1.6 e-/ADU (other binnings)
System read noise 12 e- RMS (LN read)
  14 e- RMS (standard read)
Full frame download 14.9 s (LN read)
  11.2 s (standard read)

G3-11000 electronics specification

Notes:

  1. Binning can be combined independently on both axes

  2. LN read noise depends on the CCD chip itself. If the read noise of the particular chip is 11.5 e- RMS, the system read noise is also 11.5 e- RMS.

  3. Download times can be somewhat longer when connected to USB 1.1 host.

Power and USB connectors on the bottom of the camera head

Power and USB connectors on the bottom of the camera head

Chip Cooling

Regulated thermoelectric cooling is capable to cool the CCD chip from 45 to 50 °C below ambient temperature, depending on the camera type. The Peltier hot side is cooled by a fans. The CCD chip temperature is regulated with ±0.1 °C precision. High temperature drop and precision regulation ensure very low dark current for long exposures and allow proper image calibration.

G3 cameras are available in two variants, differing in the cooling performance:

  • Standard cooling cameras achieve temperature difference up to 45 °C Under environment temperature.

  • Enhanced cooling cameras can regulate temperature up to 50 °C under environment temperature. Compared to standard variant, enhanced cooling cameras are somewhat bulkier due to bigger heat sink, slightly heavier and somewhat noisier because of more powerful fans.

CCD chip cooling Thermoelectric (Peltier modules)
Standard cooling ΔT 48 °C below ambient maximum
  45 °C below ambient typical
Enhanced cooling ΔT 53 °C below ambient maximum
  50 °C below ambient typical
Regulation precision 0.1 °C
Hot side cooling Air cooling (two fans)
  Optional liquid coolant heat exchanger

Chip cooling specifications

Comparison od the heat sink of standard (left) and enhanced (right) cooling cameras

Comparison od the heat sink of standard (left) and enhanced (right) cooling cameras

Notes:

  1. It is not recommended to cool the chip to the maximum temperature difference, else the camera cannot guarantee temperature stability when the ambient air temperature rises. It is usually practical to set the temperature so the cooling utilization varies around 90%. This provides enough reserve in cooling power to keep the CCD temperature even if the ambient temperature rises several degrees Celsius.

  2. The cooling performance depends on the environmental conditions and also on the power supply. If the power supply voltage drops below 12 V, the maximum temperature difference is lower.

Maximum temperature drop -50°C achieved with approx. 75% cooling utilization

Maximum temperature drop -50°C achieved with approx. 75% cooling utilization

Power supply

The 12 V DC power supply adapter enables camera operation from arbitrary power source including batteries, wall adapters etc. Universal 100–240 V AC/50–60 Hz, 60 W “brick” adapter is supplied with the camera.

Camera head supply 12 V DC
Camera power consumption 15 W without cooling
  52 W with 100% cooling
Power connector 5.5/2.5 mm, center +
Adapter input voltage 100-240 V AC/50-60 Hz
Adapter output voltage 12 V DC/5 A
Adapter maximum power 60 W

Power supply specifications

Notes:

  1. Camera power consumption is measured on the AC outlet of the 12 V power supply.

  2. The camera contains its own power supplies inside, so it can be powered by unregulated 12 V DC power source — the input voltage can be anywhere between 10 and 14 V. However, some parameters (like cooling efficiency) can degrade if the supply drops below 12 V.

  3. G3 CCD camera measures its input voltage and provides it to the control software. Input voltage is displayed in the Cooling tab of the CCD Camera control tool in the SIPS. This feature is important especially if you power the camera from batteries.

12 V DC/5 A power supply adapter for G3 Camera

12 V DC/5 A power supply adapter for G3 Camera

Warning:

The power connector on the camera head uses center-plus pin. Although all modern power supplies use this configuration, always make sure the polarity is correct if you use own power source.

Mechanical Specifications

Compact and robust camera head measures only 154 × 154 × 65 mm (approx. 6 × 6 × 2.6 inches). A variant with internal filter wheel is thicker and measures 77.5 mm (approx. 3 inches). The head is CNC-machined from high-quality aluminum and black anodized. The head itself contains USB-B (device) connector and 12 V DC power plug, no other parts (CPU box, USB interface, etc.), except a “brick” power supply, are necessary. Integrated mechanical shutter allows streak-free image readout, as well as automatic dark frame exposures, which are necessary for unattended, robotic setups. Optional integrated filter wheel contains 5 positions for standard 2" threaded filter cells with M48 × 0.75 thread or up to 50.8 mm “glass-only” filters.

G3 CCD camera with internal filter wheel

Internal mechanical shutter Yes, blade shutter
Shortest exposure time 0.2 s
Longest exposure time Limited by chip saturation only
Internal filter wheel (optional) 5 positions for 2" threated cells M48 × 0.75 or D50 mm unmounted filters
Standard cooling head dimensions 154 mm × 154 mm × 65 mm (without filter wheel)
  154 mm × 154 mm × 77.5 mm (with internal filter wheel)
Enhanced cooling head dimensions 154 mm × 154 mm × 76 mm (without filter wheel)
  154 mm × 154 mm × 88.5 mm (with internal filter wheel)
Back focal distance 16.5 mm (without filter wheel)
  29 mm (with internal filter wheel)
  33.5 mm (with external filter wheel)
Standard cooling head weight 1.6 kg (without filter wheel)
  1.9 kg (with internal filter wheel)
  2.5 kg (with internal filter wheel)
Enhanced cooling head weight 1.8 kg (without filter wheel)
  2.1 kg (with internal filter wheel)
  2.7 kg (with internal filter wheel)

Mechanical specifications

Regardless if the camera has standard or enhanced cooling or if it is equipped with internal filter wheel or not, the front view dimensions are the same. Also mounting adapter holes are the same, so both camera variants are compatible with the same set of telescope/lens adapters.

The only different dimension is the camera thickness. Enhanced cooling requires thicker camera back shell.

G3 camera head front view dimensions

G3 camera head front view dimensions

Dimensions of G3 camera with standard cooling and internal filter wheel

Dimensions of G3 camera with enhanced cooling and internal filter wheel

Variants without and with internal filter wheel have different front shell thickness, which brings different Back Focal Distance, but mechanical spacers, compensating for different BFD are available (see the system diagram in the “G3 Camera Overview” sub-chapter above).

G3 camera head with external filter wheel front view dimensions

G3 camera head with external filter wheel front view dimensions

Dimensions of G3 camera with standard cooling and external filter wheel

Dimensions of G3 camera with enhanced cooling and external filter wheel

Optional accessories

Camera head can be combined with various accessories according to the requirements of the target application (optical system, used filters, guiding, etc.).

Telescope Adapters

Various telescope and lens adapters for the G3 cameras are offered. Users can choose any adapter according to their needs and another adapters can be ordered separately.

It is possible to choose from the following telescope/lens adapters:

2" barrel adapter
Adapter for 2" focusers.

T-thread short
M42 × 0.75 inner thread, 7.5 mm thick.

T-thread with 55 mm BFD
M42 × 0.75 inner thread.
Preserves 55 mm back focal distance.

M48 × 0.75 thread short
M48 × 0.75 inner thread, 7.5 mm thick.

M48 × 0.75 thread with 55 mm BFD
M48 × 0.75 inner thread.
Preserves 55 mm back focal distance.

Pentax (Praktica) lens adapter
M42 × 1 mm inner thread.
Preserves 45.5 mm back focal distance.

M68 × 1 thread adapter
Adapter with inner thread M68 × 1.

Canon EOS lens adapter
Standard Canon EOS bayonet adapter.

Nikon F lens adapter
Standard Nikon F bayonet adapter.

3” Wynne adapter
Adapter for 3” coma-corrector ASA Wynne.

3” Paracorr BIG adapter
Adapter for 3” coma-corrector TeleVue Paracorr BIG, intended for attaching to EFW with M68×1.

3” Paracorr BIG adapter
Adapter for 3” coma-corrector TeleVue Paracorr BIG, intended for G3-OAG.

If the mounting standard defines also back focal distance (distance from adapter front plane to detector), the particular adapter is constructed to preserve defined distance (for instance T-thread defines back focal distance to 55 mm, but certain distance is defined also for Pentax (Praktica) thread, for Canon EOS and Nikon bayonets etc.).

Adapters are attached to the camera body using four M3 (3 mm metric) screws. These threaded holes are placed on the corners of 44 mm square. Custom adapters can be made upon request.

External Filter Wheels

When there is no filter wheel inside the camera head, all electronics and firmware, intended to control it, stays idle. These components can be utilized to control external filter wheel with only little changes. Also the camera front shell can be manufactured thinner, the space for filter wheel is superfluous.

7-positions External Filter Wheel for the G3 camera

External filter wheels are described in detail here.

Off-Axis Guider adapter

The G3 off-axis guider (OAG) is designed to allow attachment of any guiding camera with 1.25" eyepiece nose, although the nose must be somewhat shorter to achieve focus. G0 cameras are designed to achieve focus with G3 OAG and a special shorter version of 1.25" nose with C-mount thread is available for all G1 cameras. Any camera with CS-mount (short version of C-mount standard) can use this adapter to be attached to G3 OAG.

The G3 OAG offers the M68 × 1 thread on the telescope side. The back focal distance is 61.5 mm.

G3 Off-Axis Guider Adapters

Off-Axis Guider adapters are described in detail here.

Guiding cameras

G0 and G1 cameras are completely independent devices with their own USB connection to the host PC. They are mentioned here only not to omit an important part of the whole system.

G1-0301 standalone guiding/imaging camera is equipped with USB connection and standard “AutoGuider” port

G0 and G1 cameras can be used on the G3 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 with up to 3 other Gx cameras to be accessed over network.

G0 and G1 guider cameras are described in detail here.

Attaching camera head to telescope mount

G3 cameras are equipped with two “tripod” 0.250-20UNC threads on the top side of the camera head. This thread can be used to attach 1.75 inch “dovetail bar” (Vixen standard). It is then possible to attach the camera head, e.g. equipped with photographic lens, directly to various telescope mounts supporting this standard.

1.75" bar for standard telescope mounts

1.75" bar for standard telescope mounts

Spare desiccant containers

The G3 cameras are supplied with silicagel container, intended to dry the CCD cold chamber. This container can be unscrewed and desiccant inside can be dried in the owen (see the camera User's Manual).

Remark:

This is why the container itself does not contain any sealing, which could be damaged by high temperature in the owen. The sealing remains on the CCD cold chamber instead.

Container shipped with the camera by default does not exceed the camera head outline. It is equipped with a slot for tool (of for just a coin), allowing releasing and also tightening of the container. Containers intended for enhanced cooling cameras are prolonged as the camera thickness is greater in the case of this variant.

Containers for standard and enhanced cooling cameras also in variants allowing tool-less manipulation

Containers for standard and enhanced cooling cameras also in variants allowing tool-less manipulation

It is possible to order spare container, which makes desiccant replacement easier and faster. It is possible to dry the spare container with silicagel and then only to replace it on the camera. Spare container is supplied including the air-tight cap.

Spare container can be supplied also in variant, allowing manipulation without tools. But this container is longer and exceeds camera outline. If the space behind the camera is not critical, this container can make desiccant exchange even easier.

Silicagel container with slot (left) and for tool-less manipulation (right)

Camera head color variants

Camera head is available in several color variants of the center plate. Visit manufacturer's web pages for current offering.

G3 camera color variants

Gx Camera Ethernet Adapter

Gx Camera Ethernet Adapter allows connection of up to 4 Gx cameras of any type on the one side and 1 Gbps Ethernet on the other side. This adapter allows access to connected Gx cameras using routable TCP/IP protocol over practically unlimited distance.

The Gx Camera Ethernet Adapter is available in several variants, but their functionality is basically the same

Gx Camera Ethernet Adapter devices are described in detail here.

Software Support

Powerful SIPS (Scientific Image Processing System) software supplied with the camera allows complete camera control (exposures, cooling, filters) with automatic sequences and complete image calibration. SIPS also supports advanced tools like Image Add tool with automatic sub-pixel image alignment, (L)RGB Add tool, Image Blink tool, image filters and many more functions.

Scientific Image Processing System

SIPS software package is freely available for download from this www site.

Drivers for ASCOM standard as well as native drivers for third-party software are also available (e.g. TheSkyX, MaxIm DL, AstroArt, etc.). Visit the download page of this web site for current list of available drivers, please.

Automatic guiding

SIPS software package allows automatic guiding of the astronomical telescope mounts using separate guiding camera. Proper and reliable automatic guiding utilizing the computational power of Personal Computer (e.g. calculation of star centroid allows guiding with sub-pixel precision) is not simple task. Guiding complexity corresponds to number of parameters, which must be entered (or automatically measured).

The SIPS Guider tool window

The SIPS “Guider” tool window

The “Guiding” tool allows switching of autoguiding on and off, starting of the automatic calibration procedure and recalculation of autoguiding parameters when the telescope changes declination without the necessity of new calibration. Also swapping of the German Equatorial mount no longer requires new autoguider calibration. There is also a graph showing time history of guide star offsets from reference position in both axes. The length of graph history as well as the graph range can be freely defined, so the graph can be adjusted according to particular mount errors and periodic error period length. Complete log of calibration procedure, detected offsets, correction pulses etc. is also shown in this tool. The log can by anytime saved to log file.

An alternative to classic autoguiding is the inter-image guiding, designed for modern mounts, which are precise enough to keep tracking with sub-pixel precision through the single exposure, and irregularities only appear on the multiple-exposure time-span. Inter-image guiding then performs slight mount position fixes between individual exposures of the main camera, which eliminates “traveling” of the observed objects through the detector area during observing session. This guiding method uses main imaging camera, it does not use another guiding camera and naturally does not need neither OAG nor separate guiding telescope to feed the light into it.

Inter-image guiding controls in the Guiding tab of the Imager Camera tool window

Inter-image guiding controls in the Guiding tab of the Imager Camera tool window

Advanced reconstruction of color information of single-shot-color cameras

Color CCD detectors have red, green and blue filters applied directly on individual pixels (so-called Bayer mask).

Schematic diagram of color CCD detector with Bayer mask (left) and magnified crop of raw image captured by color camera (right)

Every pixel registers light of particular color only (red, green or blue). But color image should contain all three colors for every pixel. So it is necessary to calculate missing information from values of neighboring pixels.

There are many ways how to calculate missing color values — from simple extending of colors to neighboring pixels (this method leads to coarse images with visible color errors) to methods based on bi-linear or bi-cubic interpolation to even more advanced multi-pass methods etc.

Bi-linear interpolation provides significantly better results than simple extending of color information to neighboring pixels and still it is fast enough. But if the telescope/lens resolution is close to the size of individual pixels, color artifacts appear close to fine details, as demonstrated by the image below left.

The above raw image with colors calculated using bi-linear interpolation (left) and the same raw image, but now processed by the multi-pass de-mosaic algorithm (right)

Multi-pass algorithm is significantly slower compared to single-pass bi-linear interpolation, but the resulting image is much better, especially in fine details. This method allows using of color camera resolution to its limits.

SIPS offers choosing of color image interpolation method in both “Image Transform” and “New Image Transform” tools. For fast image previews or if the smallest details are significantly bigger than is the pixel size (be it due to seeing or resolution of the used telescope/lens) the fast bi-linear interpolation is good enough. But the best results can be achieved using multi-pass method.

Shipping and Packaging

G3 CCD cameras are supplied in the foam-filled, hard carrying case containing:

  • Camera body with a user-chosen telescope adapter. The standard 2" barrel adapter is included by default. If ordered, the filter wheel is already mounted inside the camera head and filters are threaded into place (if ordered).

  • A 100-240 V AC input, 12 V DC output “brick” adapter with 1.8 m long power cable.

  • 5 m long USB A-B cable for connecting camera to host PC.

  • USB Flash Drive or CD-ROM with camera drivers, SIPS software package with electronic documentation and PDF version of User's Manual.

  • A printed copy of User's Manual.

G3 and G4 CCD cameras are shipped in the foam-filled carrying case (left), larger case is used if camera is ordered with external filter wheel (right)

Image Gallery

Example images captured with G3 cameras.

Object M65, M66 a NGC 3628 “Leo Triplet”
Author Martin Myslivec
Camera G3-16200
Filters LRGB
Exposure 34 hours
Telescope 300 mm, f/4 Newtonian telescope

Object M78 nebula
Author Martin Myslivec
Camera G3-16200
Filters LRGB
Exposure 39 hours
Telescope 300 mm, f/4 Newtonian telescope

Object NGC2237 “Rosette”
Author Martin Myslivec
Camera G3-16200
Filters Hα, OIII, SII
Exposure 31 hours
Telescope 300 mm, f/4 Newtonian telescope

Object NGC2237 “Rosette”
Author Martin Myslivec
Camera G3-16200
Filters Hα, OIII (true colors)
Exposure 16 hours
Telescope 300 mm, f/4 Newtonian telescope

Object NGC4631 “Whale Galaxy” and NGC4656 “Hockey Stick Galaxy”
Author Martin Myslivec
Camera G3-16200
Filters LRGB
Exposure 26 hours
Telescope 300 mm, f/4 Newtonian telescope

Object LDN673 “Maya Glyph” dark nebula
Author Leonardo Orazi
Camera G3-16200
Filters LRGB
Exposure 18.5 hours
Telescope FSQ-106EDXIII

Object M8 “Lagoon” and M20 “Trifid” nebulae
Author Leonardo Orazi
Camera G3-16200
Filters LRGB
Exposure 27 hours
Telescope FSQ-106EDXIII

Object NGC7023 “Iris” and VdB 141 “Ghost” nebulae
Author Leonardo Orazi
Camera G3-16200
Filters LRGB
Exposure 22 hours
Telescope FSQ-106EDXIII

Object NGC1333
Author Martin Myslivec
Camera G3-16200
Filters LRGB
Exposure 39 hours
Telescope 300 mm, f/4 Newtonian telescope

Object NGC7293 “Helix”
Author Martin Myslivec
Camera G3-16200
Filters HαOIII
Exposure 45 hours
Telescope 300 mm, f/4 Newtonian telescope

Object NGC7635 “Bubble” nebula and M52 cluster
Author Ron Brecher
Camera G3-16200
Filters HαRGB
Exposure 21 hours
Telescope 10” f/3.6 ASA astrograph

Object M27 “Dumbbell” nebula
Author Ron Brecher
Camera G3-16200
Filters RGB
Exposure 12 hours
Telescope 10” f/3.6 ASA astrograph

Object χ a h double cluster in Perseus
Author Ron Brecher
Camera G3-16200
Filters RGB
Exposure 1 hour
Telescope 10” f/3.6 ASA astrograph

Object M81 “Bode” and M82 “Cigar” galaxies
Author Ram Viswanathan
Camera G3-16200
Filters RGB
Exposure 2 hours
Telescope TEC ADL300

Object M106
Author Ram Viswanathan
Camera G3-16200
Filters LRGB
Exposure 4.5 hours
Telescope TEC ADL300

Object Markarian chan of galaxies
Author Martin Myslivec
Camera G3-16200
Filters LRGB
Exposure 25 hours
Telescope 300 mm, f/4 Newtonian telescope

Object M42 “Great Orion nebula”
Author Martin Myslivec
Camera G3-16200
Filters LRGB
Exposure ~3 hours
Telescope 300 mm, f/4 Newtonian telescope

Object M81 “Bode” and M82 “Cigar” galaxies
Author Marco Burali
Camera G3-16200
Filters LRGB
Exposure 6 hours
Telescope Takahashi BRC 250, f/5

Object VdB 141 “Ghost nebula”
Author Marco Burali
Camera G3-16200
Filters LRGB
Exposure 5 hours
Telescope Takahashi BRC 250, f/5

Object B150 dark nebula
Author Marco Burali
Camera G3-16200
Filters LRGB
Exposure 5 hours
Telescope Takahashi BRC 250, f/5

Object M65, M66 a NGC 3628 “Leo Triplet”
Author Marco Burali
Camera G3-16200
Filters LRGB
Exposure 6 hours
Telescope Takahashi BRC 250, f/5

Object M109, M97 “Owl nebula”
Author Marco Burali
Camera G3-16200
Filters LRGB
Exposure 5 hours
Telescope Takahashi BRC 250, f/5

Object NGC4631, NGC4656
Author Marco Burali
Camera G3-16200
Filters LRGB
Exposure 7 hours
Telescope Takahashi BRC 250, f/5

Object NGC1333
Author Pavel Pech
Camera G3-11000
Filters Astrodon Tru-Balance I-Series LRGB + Halpha
Telescope ASA 10" N + ASA 3" Wynne corrector
Exposure 12 hours

Object LBN552
Author Pavel Pech
Camera G3-11000
Filters Astrodon Tru-Balance I-Series LRGB
Telescope ASA 10" N + ASA 3" Wynne corrector
Exposure 8 hours

Object M31 Andromeda galaxy
Author Pavel Pech
Camera G3-11000
Filters Astrodon Tru-Balance I-Series LRGB + Halpha
Telescope ASA 10" N + ASA 3" Wynne corrector
Exposure 5 hours

Object Three nebulae in Orion: “Flame”, “Horse Head” and “Great Nebula”
Author Pavel Pech
Camera G3-11000
Filters Astrodon Tru-Balance I-Series LRGB + Halpha
Telescope Borg 77EDII + F4 ED Super Reducer
Exposure 11 hours

Object NGC7129 reflection nebula in Cepheus
Author Pavel Pech
Camera G3-11000
Telescope ASA 10" f/3.6 Newton

Object LBN 603 dark nebula
Author Pavel Pech
Camera G3-11000
Telescope ASA 10" f/3.6 Newton

Object “Hoese head” and “Flame” nebulae in Orion (H-alpha + OIII)
Author Jonas Fiedler
Camera G3-11000
Telescope Takahashi FSQ 106

Object M106 (H-alpha + LRGB)
Author Pavel Pech
Camera G3-11000
Telescope Celestron C11 Edge HD

Object Sard region in Cygnus (bi-color H-alpha a OIII)
Author Pavel Pech
Camera G3-11000
Telescope Borg 77EDII + Borg F4 ED Super Reducer

Object M81 “Boode galaxy”
Author Pavel Pech
Camera G3-11000
Telescope Celestron Edge HD 11

Object “Witch head” nebula and Rigel
Author Pavel Pech
Camera G3-11000
Telescope Borg 77EDII + F4 ED Super Reducer

Object Corona Australis
Author Pavel Pech
Camera G3-11000
Telescope Borg 77EDII + F4 ED Super Reducer

Object Orion belt and “Horse head” nebula
Author Pavel Pech
Camera G3-11000
Telescope Borg 77EDII + F4 ED Super Reducer

All images published with permission of their respective authors.