Maria replied to the topic 'ASI 294 color balance?' in the forum. 1 year ago

Hi Magnus,

I use the ASI 294 with the default settings in KStars/EKOS/Indi and have not had issues.
eg: www.astrobin.com/pf7fo9/?nc=user

Although I don't use PixInsights for calibrations or integration phases.
Instead I use AstropixelProcessor, which I feel gives a great result and handles the "color cast" you see in PixInsight, which I believe is an artificial cast to do with how the data is written perhaps.
Additionally, I also recommend doing Dark Flat instead of Bias frames with this sensor (this topic has been quite hot around this sensor, check the forums. As the sensor does not behave consistently at with sub-second frames)

When opening my source images in PixInsight I can confirm I get the same blue cast you describe, but this does not affect the final integration which AstropixelProcessor seems to handle well.

One question, as I expect PixInsights should integrate the channels separately, can you apply a HistogramTransform afterwards, but without the "Link RGB Channels" icon enabled. This can be found on the ScreenTransferFunction tool.
When I do this with the "Link RGB Channels" disabled, the result is a normal averaged to grey image (it is color, although the color cast has gone!)
So perhaps calibrate & integrate as normal, but apply an unlinked HistogramTransformation

I have questioned this myself in the past and played at setting these values, but found little difference in my resulting integrated images.
Also I suspect the defaults (in indi panel, WB_R: 52, WB_B: 95) have something to do with the Bayer array and sensitivity of sensor to those color relative to Green.

Hope this helps.
Regards
Maria

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