Dear All

I have a new QHY294M-Pro which I am trying to connect through KStars/ECOS (v3.5.1 Stable, Build from Jan 8th 21) with the the latest Indi compiled from the GIT master repository and QHYSDK version 20-12-11-15. Connectivity and general camera control all work well. But the image resolutions that I am getting from the Indi-qhy driver look odd which is what I would like to share here in this forum and hear from others if they might have had similar observations:

For one, I can't seem to get the alternative read mode for the higher pixel resolution supported by the camera to work through Indi and for the other, it isn't clear to me how the overscan areas of the sensor are meant to be supported.

The driver options do let me toggle between the two different read modes. When the camera is switched to the "47M" read mode (read mode = 1) the SDK does seem to report the higher read mode resolution of 8336x5648 px out to the driver. However then it seems that the SDK/driver scales the image resolution back to what seems to be the effective image region of the "11M" (read mode = 0) resolution which is 4164x2795 px. That is then also the resolution I am getting for the downloaded FITS image. The log also indicates this:

2021-02-02T04:04:08: [INFO] GetQHYCCDReadModeResolution in this ReadMode: imageW: 4164 imageH: 2795
2021-02-02T04:04:08: [INFO] GetQHYCCDReadModeResolution in this ReadMode: [ imageW: 8336 > imageEAW: 4164 ] / [ imageH: 5648 > imageEAH: 2795 ]
2021-02-02T04:04:08: [INFO] Read mode updated to 1
2021-02-02T04:04:08: [INFO] GetQHYCCDEffectiveArea: subX :36 subY: 28 subW: 4164 subH: 2795

This seems to be the frame area without overscan area and without optic black area.

In the 11M read mode the resulting image has a final resolution of 4164x2822 px and thus does seem to include the overscan area to the bottom of the frame.

2021-02-02T04:06:59: [INFO] GetQHYCCDReadModeResolution in this ReadMode: imageW: 4164 imageH: 2822
2021-02-02T04:06:59: [INFO] Read mode updated to 0

to compare against recording frames with the different read modes through EZCAP the image resolution I am getting (here by choosing to not ignore the overscan area) for the 11M mode is 4212x2822 px. Thus this includes the overscan area at the bottom of the frame and the optic black area at the left side of the frame. In the 47M mode the frame has a resolution of 8432x5648 px, thus also including overscan and optic black areas.

My thoughts are that this should also be the correct behavior for the indi-qhy driver... Perhaps with an additional driver option to include or ignore the overscan areas?

Another point that caught my eye is that the driver/SDK does not seem to support the amp glow reduction mode which the camera should be able to turn on and off according to the manual for the 294M from the QHY website. This sounds more like a question for the QHY support though.

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