Moravian C3-PRO-26000EC Mono CMOS Camera - Sensor D=28,3 mm

C3 Series CMOS Cameras

C3 cameras employ the latest generation of Sony IMX CMOS sensors, offering exceptional quantum efficiency thanks to back-illuminated design and very low dark current. Despite relatively small pixels, full-well capacity exceeds 50 ke-. Combined with full 16 bit digitization, perfectly linear response to light and exceptionally low read noise, these cameras are suitable for both aesthetic astro-photography as well as astronomical research. Sensor formats from APS to photographic full-frame (24 × 36 mm) ensure wide field of view and optimally utilize capabilities of the optical systems most commonly used by amateur astronomers.

Mechanical design of the C3 series of astronomical CMOS cameras inherits from earlier CCD-based G3 Mark II cameras, which makes the C3 camera line fully compatible with vast range of telescope adapters, off-axis guider adapters, filter wheels, Ethernet adapters, guiding cameras etc.
Rich software and driver support allow usage of C3 camera without necessity to invest into any 3rd party software package thanks to included free SIPS software package. However, ASCOM (for Windows) and INDI (for Linux) drivers and Linux driver libraries are shipped with the camera, provide the way to integrate C3 camera with broad variety of camera control programs.
The C3 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 cooled cameras usually require computer for operation control, image download, processing and storage etc.
C3 cameras are designed to be attached to host PC through very fast USB 3.0 port. While C3 cameras remain compatible with older (and slower) USB 2.0 interface, image download time is significantly longer.

C3 cameras are equipped with Sony IMX rolling shutter back-illuminated CMOS detectors with 3.76 × 3.76 μm square pixels. Despite the relatively small pixel size, the full-well capacity over 50 ke- rivals the full-well capacity of competing CMOS sensors with much greater pixels and even exceeds the full-well capacity od CCD sensors with comparable pixel size.
The used Sony sensors are equipped with 16-bit ADCs (Analog to Digital Converters). 16-bit digitization ensures enough resolution to completely cover the sensor exceptional dynamic range.

Exposure control
The shortest exposure time of the C3 cameras depends on the used sensor type:
C3-26000 shortest exposure is 17.3 μs
C3-61000 shortest exposure is 19.5 μs
There is no practical limit on maximal exposure length, but in reality, the longest exposures are limited by saturation of the sensor either by incoming light or by dark current (see the following chapter about sensor cooling).

Mechanical shutter
C3 cameras are equipped with mechanical shutter, which is very important feature allowing unattended observations (fully robotic or just remote setups). Without mechanical shutter, it is not possible to automatically acquire dark frames, necessary for proper image calibration etc.
Mechanical shutter in the C3 cameras is designed to be as reliable as possible, number of open/close cycles is virtually unlimited, because there are no surfaces rubbing against each other. The price for high reliability is slow shutter motion. Luckily, mechanical shuttering is not necessary for exposure control, only for taking dark frames and possibly bias frames — all used CMOS sensors are equipped with electronic shuttering.
Camera firmware optimizes the shutter operation to avoid unnecessary movements. If a series of light images is taken immediately one after another, the shutter remains open not to introduce quite significant delay of the close/open cycle between each pair of subsequent light images. In the case next image has to be dark or bias frame, shutter closes prior to dark frame exposure and vice versa — shutter remains closed if a series of dark frames is acquired and opens only prior to next light frame. If no exposure is taken for a few seconds while the shutter is open (this means after a light image exposure), camera firmware closes the shutter to cover the sensor from incoming light.

Cooling and power supply
Regulated thermoelectric cooling is capable to cool the CMOS sensor from 40 to 45 °C below ambient temperature, depending on the camera type. The Peltier hot side is cooled by fans. The sensor 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.
C3 cameras are available in two variants, differing in the cooling performance:
Standard cooling cameras achieve regulated temperature difference up to 40 °C under environment temperature.
Enhanced cooling cameras can regulate temperature up to 45 °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.

Note: Some pictures show accessories which are not included in the scope of delivery.