Testing the low cost SVBONY SV105 camera with AstroDMx Capture for Linux

The SVBONY SV105 camera was purchased from the SVBONY store on AliExpress for £36. Delivery was fast, taking about a week and the tracking information was first rate.
The camera comes well boxed

The camera is supplied with a USB cable and a dust cap for the front of the built in telescope adapter.
The camera is very well built with a metal housing.

The inside of the camera is sealed by a built in optical window and it is recommended not to unscrew the adapter and allow air inside.

The sensor is a 1/3" 2Mpixel (1920 x 1080) colour CMOS OV2710 sensor with 3µm x 3µm pixels. The camera consumes 150mA at 5volts.

Initial tests have been done in daylight. and the first thing to notice is that the camera suffers from the reverse pixel vignetting that we have discussed in relation to other cameras, but which can be rectified by flat-field correction.

An average flat field was produced using AstroDMx Capture for Linux.

The reverse vignetting is clearly evident, with the lighter regions being around the periphery of the image.
This is the log file for the production of the average flat field frame by AstroDMx Capture for Linux

 AstroDMx Capture for Linux was used with real-time flat-field correction and this demonstrates that the flat-field correction rectifies the reverse pixel-vignetting.

Animation showing the correction of the reverse vignetting

The image is of an area on the other side of the valley, taken through an 80mm ED refractor.

The camera only produces output in Motion Jpeg format, but AstroDMx Capture for Linux extracts data from the video stream at the highest possible quality, so any possible problems are minimised. We have discussed Motion Jpeg in a previous post, and it is possibly the best mode of compression if any compression is imposed on the video stream. This is because each frame is separately compressed, with no reference to the contents of other frames. In an image with lots of detail, the Jpeg compression should be minimal. It is best to have no compression for astronomical imaging.

This is how the SVBONY SV105 camera presents itself with the Terminal command
 v4l2-ctl --all -d /dev/video1

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As a separate bit of news: Nicola has now implemented FITs file capture in AstroDMx Capture for Linux. The software can now capture:

• Greyscale FITs
• Separate FITs files for each colour channel
• Genuine colour FITs images with all of the colour channels in a single FITs file

Nicola will shortly be releasing another version of AstroDMx Capture for Linux incorporating the FITs capture.