Color CCD ASI533 MC Pro normal look

[Tracy]

This has happened with both of my recent captures with the ASI533MC Pro.
I'm used to seeing (at times) a green cover... but never have seen blue. This was a simple stacked image in PI of M81 using about 28 120s captures.

 

[Tracy]

This is what I've gotten so far, and still am working on tweaking. I don't know why it's blue when others have been green tinted with the ASI533MM Pro.
One thing I noticed was a thin high layer of clouds were coming in... and shortly after the last shot of this sequence you couldn't see anything.

 

[OhNo]

What debayering matrix are you using? I believe it is supposed to be RGGB

 

[Tracy]

What debayering matrix are you using? I believe it is supposed to be RGGB

I’ll have to check. It’s whatever PI sets as a default though since I haven’t messed with it. Thanks for a point to check it out.

 

[OhNo]

When I use my 533MC P I never use PIx, I always use APP.

 

[Tracy]

When I use my 533MC P I never use PIx, I always use APP.

I tried using APP last night... and usually when I process in PI I use PCC after stretching when I've shot a galaxy. Found that if I stacked in APP then I could not use PCC (photometric color calibration) in PI because apparently APP strips the astrometric solution data when it creates its final file?
I have yet to find anywhere in PI that controls any debayer layering during stacking.

 

[Stan]

Use this script to put the astrometric data back in

 

[Stan]

 

[Tracy]

Use this script to put the astrometric data back in

Worked like a champ! Thanks for bringing that to my attention.

 

[Stan]

Worked like a champ! Thanks for bringing that to my attention.

Happy to help when I can

 

[Tracy]

A few more (about 30) captures and about 10 minutes spend in PI... and I missed several steps in the processing.. trying to do it from memory.

Once more... all in PI (and the blue on the stretch is still present). This one did have bias and flats done for it... I am going to try processing it also with the bias and only use the flats.

M81/M82 quick try

• Tracy
• January 25, 2023

Added some more captures to this sequence and this was a quick down & dirty procesing.

 

[Tracy]

And a little tighter crop.

 

[Tracy]

Coming back to this... all the images when stretched in PI (using Screen Transfer) appear like this.
They do not when stacked in other software.... and yes, the bayer matrix is RGGB.
I'm wondering if it may have something to do with the fact I'm using no filters at all. I have rad some that cyan or green can show up when you have stacked an series of captures then stretch them.