Moravian C1-5000A Mono CMOS camera and autoguider -- Sensor D=11.1 mm

C1 Series CMOS Cameras

The C1 series cameras with global shutter CMOS sensors were designed to be small, lightweight imagers for Moon and planets and for automatic telescope guiding. With proper image calibration, C1 cameras provide surprisingly good results also in entry-level deep-sky imaging. The used CMOS sensors response to light is linear up to very close to saturation point, so, C1 cameras can be used for scientific applications like variable star research, too.
C1 camera models are equipped with Sony IMX global shutter CMOS detectors with 3.45 × 3.45 μm square pixels. Individual models differ in resolution only.
All used sensors utilize global electronic shutter. This means every pixel within the image is exposed in the same time, as opposed to rolling shutter sensors, which exposes individual lines one after another. There is no difference for long exposures of static objects, but imaging of moving objects using short exposure time using rolling shutter leads to image shape distortions.

The C1 cameras are designed to work in cooperation with a host Personal Computer. As opposite to digital still cameras, which are operated independently on the computer, the scientific cameras usually require computer for operation control, image download, processing and storage.
C1 cameras are designed to be connected with the host PC through USB 3.0 interface, operating at 5 Gbps. Cameras are also compatible with USB 2.0 port to communicate with a host PC.

The C1 cameras do not need an external power supply to operate, they are powered through the USB connection from the host PC.

Exposure control
C1 cameras are capable of very short exposures. The shortest exposure time is 125 μs (1/8000 of second). This is also the step, by which the exposure time is expressed. So, the second shortest exposure is 250 μs etc.
Long exposure timing is controlled by the host PC and there is no upper limit on exposure time. In reality the longest exposures are limited by saturation of the sensor either by incoming light or by dark current (see the following sub-chapter).

Sensor Cooling
Dark current is an inherent feature of all silicone circuits. It is called “dark”, because it is generated regardless if the sensor is exposed to light or not. Dark current, injected into individual pixels, appear in image as noise. The longer exposure, the greater amount of noise is present in every image. As it is generated by random movement of particles, it depends on the temperature exponentially (this is why the noise generated by dark current is also denoted “thermal noise”). Typically, lowering the sensor temperature by 6 or 7 °C halves the dark current.
While the C1 cameras are not equipped with active thermo-electric (Peltier) cooling, they are still equipped with a small fan, exchanging the air inside the camera body. What´s more, a small heat sink is located directly on the sensor (with the exception of the C1-1500 model, which sensor is too small for heat sink) to remove as much heat as possible. So, the C1 sensor cannot be cooled below the ambient temperature, but its temperature is kept as close to environment as possible. Compared to closed designs, the sensor temperature in the C1 camera can be up to 10°C lower and resulting dark current may be less than half.

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

Safety informations: PDF Download