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Bias Frames Not Possible?

ZWO ASI533MC ZWO ASIAIR Plus CMOS Bias Frames
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Travis McGeehan avatar
Travis McGeehan avatar
I seem unable to get reasonable bias frames out of the ASI533mc. Both the live view bias stack from ASIAir plus and the individual subframes from autorun mode have an average value around 2800, around the same point as the dark frames. This happens with both the default .001s exposure value and trying to use the camera's minimum of .000032.

Is it just not possible to use bias frames with this camera? I've seen that it's not very necessary before but I didn't realize they strictly wouldn't work.
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wsg avatar
wsg avatar
Have you tried the Auto flat/ auto bias feature?

https://eastwindastro.blogspot.com/2021/03/asiair-autoflat-frame-exposures.html
Kristof Vandebeek avatar
Kristof Vandebeek avatar
I have the 533MM and my bias frames have an average ADU value of 2800 at a gain of 105, same as the darks. I use bias frames to calibrate my flats and dark frames to calibrate my lights - this works as intended. Why do you think the similar ADU value is an issue?
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Travis McGeehan avatar
Travis McGeehan avatar
I think I figured out my problem - if you try to apply bias to lights in Siril it makes the lights go negative, you need to apply the bias correction only to the flats and then apply dark and flat to the lights.
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