I'm getting terrible pictures with this Player One camera, can someone help?

Nothing wrong, apart from the flats (except one!!).

andrea tasselli:
Nothing wrong, apart from the flats (except one!!).

Andrea,

Thanks for looking into this.  You've created a much better stacked image than what I get with WBPP.   Can you share the details on how you created it?

Thanks.

andrea tasselli:
That's all. The critical bit is in creating the right flat. The one that works is the HCG one, the others are rubbish.

Okay, herein lies the problem and makes me believe the camera DOES have a defect.

The lights were taken in HDR mode, GAIN 0, Offset 50  (which produces a bias of 200 adu)
The "lumpy" flats were taken in HDR mode, GAIN 0, Offset 50 (which matches the lights)
The HGC flats were taken in "normal" mode, GAIN 125, Offset 3 (which produces a bias of 192 adu)
So the "best" result was with flats taken in a completely differently operating mode than the corresponding BIAS and LIGHTS.  That doesn't make sense.

Here's a lumpy flat in HDR mode:



And here's the same area of the sensor in HGC mode:



The fact that a better result was produced by the second flat than the first shows in dim light (LIGHTS) the sensor's response is more like the second flat than the first.

If this camera's pixel's response to flat frames brightness (50% max ADU)  is different than those very same pixel's response to light frames (maybe 0.5% max ADU) and produces "lumpy" ADUs in bright light in HDR mode but "smooth or different" ADUs in dim light in HDR mode then the camera can't be calibrated and is useless to me.

P.S.  To rule out any problems with my flat panel I took flats with a different panel, a tracing table, and sky flats through a tee-shirt.   All of them produced the same lumpy flats which leads to the blotchy backgrounds.  The problem is not the flat light source.

The problem with the IMX585 is that it's full well exceeds the resolution of it's 12-bit ADC so I believe the chip has two separate 12-bit ADC circuits with 2 different pre-amps feeding the ADCs.  The HGC ADC has less read-noise and the LCG ADC higher read noise.

I think they way HDR mode is implemented on the IMX585 is that both the LCG and the HCG ADCs are activated simultaneously and since they have different analog pre-amps they can be tuned to convert different ranges of the analog voltage read out of the camera's pixel-well and when the ADU values from each ADC are combined in a certain way it can produce a result as if it were a single 16-bit ADC.

In HDR mode a single picture can have ADU values spanning the entire 16-bit range;  some very dark and some very bright (that's the whole point of this mode).   I can't see a way to take reverse the HDR computation and sperate the pixels in the images into ones coming from the HGC ADC and other coming from the LCG ADC and apply different flat correction to each of them … and I shouldn't have too.

For a camera to be useful for astrophotography it's ADC's have to behave in a predicable way so that the image can be calibrated and that's not what's happing with my camera.

If all owners of these PlayerOne cameras were experiencing what I'm experiencing I think we'd have heard of it by now, so this leads me to believe that my camera in particular is behaving differently than the others  and hence is defective and being defective I would expect Player One to stand behind their product and honor their warranty.

That's not what's happening here for a $600 camera to it doesn't bode well for any problems that might arise on their $3500 cameras and if you can't trust a manufacturer to stand behind it's products then it's always my recommendation to buy elsewhere.   This is surprising to me because to my knowledge I'm the only Player One customer that I know of who's been getting the brush off.  Other people have reported very responsive and accommodating customer support from Player One.