TOPIC: little problem with QHY165C camera

The following result is obtained on an armv7l device (Tinkerboard). I don't understand where it can comes from.
I have tried to capture a sequence, and each image have an identically offset.
Did you get similar results with QHY CMOS devices ?

That's not a little problem, it's huge! I will check with my QHY168C today but I haven't seen anything like that before.

I had the same issue reported with my DMK, but could not delve into the problem. No idea if it's related, but at the time it seemed to me it was a Linux USB driver issue. Issue is closed on github for this for the time being.

-Eric

Hum, if this is a Linux USB driver issue I don't understand why it happens with that camera and not with an DSLR.
And also why it doesn't happen on other hardware platforms.
Jasem, would it be useful to warn QHY about this problem ?
Pat

I don't have the problem with QHY168C. There is a new QHY SDK out now (in nightly PPA builds) so you can try that.

I made an update with the nightly build and the result is the sale on 10 captures of 10s only 4 are good and 6 show and offset on the frame.
Looks like some problem of sync or transfer speed.There is on this cams a 128Mb buffer. Isn't it to speed up transfer and prevent those problems ?

Hi,
I maintain QHYCCD's source code, so I will look at this problem especially on ARM V8 inside the RPI3 and Odroid XU4.
Otherwise, the SDK stuff works well with Ubuntu linux on my machines with I5 & I7 processors. Previously, I have tested the
QHY168C also on RPI3/XU4 with TheSkyX and it worked properly. Maybe something went wrong, so please give a a few days
to check that. We just released a new version of sdk 2.0.1 and Jasem will test it too.
BTW, we had serious problems to run larger QHY cameras on RPI2, there is no enough memory and USB traffic was extremely slow. Camera produces a lot of data with high speed - it requires USB3 port. If USB2 is used, you may lost image data headers during USB transfer and this may be the source of problem. If I remember it well, only smaller QHY cameras, like QHY5II-L was running on RPI2.
Thanks,
Jan
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Did you set your gain to about 1000 or more? Unity gain is 3200, which is too high given the dynamic range. The dynamic range on this camera is relatively flat with gain settings out to 2500. Bruce

Not sure the gain have to do something with the viewing offset of the image. Maybe I will try to change the gain value, but I am not confident in the fact that it can solve the problem. Which one looks more as a question of synchro in reading cam memory and transfert.

The image looks like a lot of noise which is not normal for Sony CMOS cameras. To me it looks like very low gain with extreme stretch... I am the US distributor for QHY cameras. Bruce Morrell

Hello Bruce,
My question wasn't about the settings of gain and offset for the capture but the shift to left of the image that can be seen on the one I included in the beginning of the discussion.

OK cool! Jan who responded below is the right guy to follow up with.... Bruce