Since the calibration images don't fully match the properties of the light frames there is no way to correct this issue. There might be some workarounds in postprocessing where you can 'hide' the background residual artifacts but in doing so it is inevitable to remove weak real signals. For instance, I don't use noise reduction at all in my workflow to prevent damage to the week fine details of my images.
Would it be possible to trade in this camara and get another model? For instance, I am interested in the ASI071pro, are you willing to take my ASI294 and replace it with an ASI071pro? I am willing to pay shipping and price difference.
In this thread, users of the ASI294MC Pro and several people that are interested in purchasing this camera have put their questions about the cause of this artifact. Unfortunately these questions have not been responded in an adequate manner.Sean.Wang wrote:Not the cooler.wargrafix wrote:Wasn't this issue related to the tec cooler?
You told us what is NOT the cause of the artifact (the tec cooler) - so, please answer our question: what is it then?
it builds in a lot of circuit like power, PLL, AD etc.
all these circuits affect the final output of one image
if there is such noise of the camera, it comes from the sensor
we can do nothing
so don't use the CMOS camera beyond its limit
294 is a very good sensor for astrophotography
but if you need to stretch the background heavily and no noise find
CCD is a better choice for such purpose