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Too much red with AWB in Live Stack

Posted: Mon Feb 04, 2019 5:26 pm
by donboy
Hi Robin,

For a long time I have been meaning to ask about the excessive red one gets when using the Auto White Balance in LIve Stack. I constantly have to pull the red channel down. It has been this way for a very long time and not specific to the latest versions. Camera is the ASI294MC Pro. I see others with the same issue via NightSkiesNetwork broadcasts and also confirmed this in private conversations.

Don

Re: Too much red with AWB in Live Stack

Posted: Mon Feb 04, 2019 6:54 pm
by admin
Hi Don,

Which of the 2 auto white balance buttons are you using? And does it make any difference if you use the other auto white balance button or does that have other problems?

Cheers, Robin

Re: Too much red with AWB in Live Stack

Posted: Mon Feb 04, 2019 7:01 pm
by donboy
Hi Robin,

I'm referring to the AWB button in live stack that is directly below the red channel slider. I press this button after 2 stacks and recheck every now and then, and it takes care of the green and blue but the red always ends to overshoot and I have to lower the red channel value. I find the star color AWB button next to it not to be useable for what I image and thus don't have any experience with it.

P.S. - The few times I've tried using the star AWB button the color balance was way off and too blue if I remember correctly.

Re: Too much red with AWB in Live Stack

Posted: Mon Feb 04, 2019 8:23 pm
by BlackWikkett
Hi All,

Some further explanation of this. Once we get the two frames in live stacking and the live stack histogram becomes live and we press AWB the red channel slider goes to max. The display histogram also shows the red channel curve well above the other channels. The display image has an aggresive red cast. An analogy would be electric guitar at max over drive. In some instances the the next frame will bring the color balance more in line and the red channel will be at its appropriate value. It seems this initial AWB is giving the red channel an extra boost in the calculation. I usually deal with this by clicking once in the red channel and this brings the red boost back in line where it should be.

-Wikkett

Re: Too much red with AWB in Live Stack

Posted: Mon Feb 04, 2019 8:33 pm
by donboy
I don't experience subsequent AWB clicks bringing the red back in line. I find no matter when in the stacking process if I click on the AWB it will give me an imbalance showing more red on the screen and also the red curve in the Display Histogram shows the red channel to the right of the other channels.

So once I manually adjust the red channel to get white balance I don't dare click on the AWB button or otherwise I have to manually reduce the red channel.

Don

Re: Too much red with AWB in Live Stack

Posted: Wed Feb 06, 2019 7:28 pm
by admin
Hi,

Please can someone send me a frame from a problem stack that is saved 'as 16-bit stack' from the live stack save option. That will let me reproduce the issue.

Cheers, Robin

Re: Too much red with AWB in Live Stack

Posted: Wed Feb 06, 2019 7:59 pm
by donboy
How do I attach a .fits image

Re: Too much red with AWB in Live Stack

Posted: Wed Feb 06, 2019 8:07 pm
by BlackWikkett
I'm clouded out for at least the next 7 days but will be glad to provide the data if no else gets to it before then.

Also a follow up on my earlier post I have to follow my procedure every time I use AWB in live stack to get red back in line with where it should be. This procedure does not seem to work for everyone as I've watched broadcasts on NSN with varying results.

-Wikkett

Re: Too much red with AWB in Live Stack

Posted: Wed Feb 06, 2019 8:10 pm
by BlackWikkett
donboy wrote:
Wed Feb 06, 2019 7:59 pm
How do I attach a .fits image
Save it to google drive or some other file share site, then provide the share link here.

-Wikkett

Re: Too much red with AWB in Live Stack

Posted: Wed Feb 06, 2019 8:30 pm
by donboy
https://drive.google.com/open?id=19R1hA ... OZhK9ltuv3

Hope this is the type file you want. I generally don't save images that aren't adjusted. It this doesn't help I maybe able to image friday so I'll be sure to save several images that have the excessive red in them when using the AWB button.

Don

P.S. Here is a following image that was adjusted manually:

https://drive.google.com/file/d/1ryEoDC ... sp=sharing