C5 CMOS cameras
C5 camera series is designed to accommodate the latest generation of extremely large Sony IMX CMOS sensors with 100 and 150 MPx resolution and diagonal dimension up to 67 mm. Many of the used sensor properties share the exceptional features of the sensors used in the C3 series, including the 3.76 μm pixel size with the full-well capacity exceeding 50 ke-, very high quantum efficiency thanks to back-illuminated design and very low dark current. C5 sensors also offer 16 bit digitization, perfectly linear response to light and exceptionally low read noise.
C5 cameras are made in two versions: Asymmetrical version marked C5A and Symmetrical version marked C5S. Both cameras may be equipped with GPS receiver for precise exposure timing.
Asymmetrical C5A
variant look reveals the same time-proven design school of the C3 and C4 series in both outer shape and internal construction. The front cross-section of the C5A cameras is the same as the C3 and C4 series, although the used sensors are much larger. C5 head thickness corresponds to the thickness of the Enhanced Cooling versions of the earlier models. Asymmetrical models also employ mechanical shutter, allowing to capture dark or bias frames without a necessity to cover the telescope aperture.
C5A series CMOS cameras
| Model | CMOS sensor | Resolution | Pixel size | Image area |
| C5A-100M | IMX461 | 11664 × 8750 | 3.76 × 3.76 μm | 43.86 × 32.90 mm |
| C5A-150M | IMX411 | 14208 × 10656 | 3.76 × 3.76 μm | 53.42 × 40.07 mm |
Symmetrical C5S
variant main purpose is not to exceed the central obstruction of reflecting telescopes with the camera located in the primary focus. The asymmetrical variant typically overhangs the central obstruction of smaller telescopes (with ~0.4 m primary mirror diameter), despite the central obstruction of wide-field telescope is rather big. Due to mechanical constrains, the symmetrical model lacks the mechanical shutter. The symmetrical variant also contains hardware trigger input, not available on the asymmetrical cameras.
C5S series CMOS cameras
| Model | CMOS sensor | Resolution | Pixel size | Image area |
| C5S-100M | IMX461 | 11664 × 8750 | 3.76 × 3.76 μm | 43.86 × 32.90 mm |
| C5S-150M | IMX411 | 14208 × 10656 | 3.76 × 3.76 μm | 53.42 × 40.07 mm |
| Feature | Asymmetrical C5A | Symmetrical C5S |
| 100 and 150 MPx sensors | Yes | Yes |
| Compatibility with filter wheels | Yes | Yes |
| M68 and M85 tiltable adapters | Yes | Yes |
| Mechanical shutter | Yes | No |
| Optional GPS receiver | Yes | Yes |
| Hardware trigger input | No | Yes |
Asymmetrical and symmetrical model comparison
Compared to C3 and C4 cameras, both C5A and C5S series feature completely redesigned air cooling — more powerful and also quieter than even the EC variants of the C3 and C4. Also, the supplied AC/DC brick power adapter is more powerful and employs more robust power plug.
Usage of large sensors required completely new design of the telescope interface and the C5 series offers M68 × 1 threaded adapter only on the smaller 100 MPx C5 variant. Large 150 MPx version of the C5 standardizes on the M85 × 1 thread on the tiltable adapter. Like in the case of the C4 series, the internal filter wheel is not an option, external filter wheels are necessary and the C5 camera are equipped to control new EFW-5XL series of filter wheels. Huge sensors require huge 65 × 65 mm square filters and EFW-5XL-5 is designed for five such filters. The EFW-5XL-7 filter wheels for seven smaller 50 × 50 mm square filters are available for 100 MPx C5 variant with smaller sensor.
Rich software and driver support allow usage of C5 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 C5 camera with broad variety of camera control programs.
The C5 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. To operate the camera, you need a computer which:
- Is compatible with a PC standard and runs modern 32 or 64-bit Windows operating system.
- Is an x86 or ARM based computer and runs 32 or 64-bit Linux operating system.
| Remark:
Drivers for 32-bit and 64-bit Linux systems are provided, but the SIPS camera control and image processing software, supplied with the camera, requires Windows operating system. |
- Support for x64 based Apple Macintosh computers is also included.
| Remark:
Only certain software packages are currently supported on Mac. |
C5 cameras are designed to be attached to host PC through very fast USB 3.0 port. While the C5 cameras remain compatible with older (and slower) USB 2.0 interface, image download time is significantly longer.
Alternatively, it is possible to use the Moravian Camera Ethernet Adapter device. This device can connect up to four Cx (and CCD based Gx) cameras of any type (not only C5, but also C1, C2, C3 and C4) 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 WiFi adapter or other networking device to the communication path.
| Hint:
Please note that the USB standard allows usage of cable no longer than approx. 5 meters and USB 3.0 cables are even shorter to achieve very fast transfer speeds. On the other side, the TCP/IP communication protocol used to connect the camera over the Ethernet adapter is routable, so the distance between camera setup and the host PC is virtually unlimited. |
Download speed is naturally significantly slower when camera is attached over Ethernet adapter, especially when compared with direct USB 3 connection.
The camera must be connected to some optical system (e.g. the telescope) to capture images. As the C5 cameras offer really large sensors with 67 mm (150 MPx version) and 55 mm (100 MPx version) diagonals, optical system must be capable to cover such large field of view. The camera is designed for long exposures, necessary to acquire the light from faint objects. If you plan to use the camera with the telescope, make sure the whole telescope/mount setup is capable to track the target object smoothly during long exposures.
