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Why does my M92 RGB come out fine from WBPP and not my Luminance ?

Processing Luminance Deep Sky
7 replies•557 views
Roger Renberg avatar
Roger Renberg avatar
Hello, 


Trying to figure out why my Luminance come out as black and white blobs (black and white as in 1 and 0) like a mask. But my RGBs come out beautifully. 
I end up needing to do my Lum manually for it to work. What am I doing wrong ? I cant find any faults in Blink either. 

Kind regards
Roger
kuechlew avatar
kuechlew avatar
Roger, it always helps to include some images of the issue, otherwise your problem description remains somewhat abstract.

Clear skies
Wolfgang
Well Written Concise
Andy Wray avatar
Andy Wray avatar
It would be good to see what a single luminance frame looks like (stretched) before it was calibrated by WBPP and a calibrated one (also stretched).

I had a similar issue recently where my darks had been taken at a different offset to the lights;  probably not an issue here, but one thing to check.
Well Written Concise
Roger Renberg avatar
Roger Renberg avatar
Roger, it always helps to include some images of the issue, otherwise your problem description remains somewhat abstract.

Clear skies
Wolfgang

Of course- Let me upload the files. and settings. Maybe someone can spot something that I am doing wrong ? I use a QSI CCD cam. Not a CMOS. 

Integration Lum

Rejection high Lum

Rejection low Lum

Here is an example of how the RGB files look like after WBPP. 


Master dark file 

Master Bias used 

Bias frame for Lum 

And underneath are my setting for a star cluster 
Roger Renberg avatar
Roger Renberg avatar
Andy Wray:
It would be good to see what a single luminance frame looks like (stretched) before it was calibrated by WBPP and a calibrated one (also stretched).

I had a similar issue recently where my darks had been taken at a different offset to the lights;  probably not an issue here, but one thing to check.

Hello Andy, 

Check out the images win the three above. Would be great if you spot something

Cheers
Roger Renberg avatar
Roger Renberg avatar
It must seem obvious to many here but the solution for this target and these sets of images was to use linear fit clipping in integration instead of Auto. 

Now all my files look good smile Incase another noob comes along and encounters this problem smile 

Clear skies
kuechlew avatar
kuechlew avatar
Looking at the "rejection low" map it seems the auto setting rejects most of your pixels leading to the b&w effect. This is rather embarrassing. 
Did you try the with the latest version of the WBPP script too? "Auto" setting never failed on me so far.

Clear skies
Wolfgang
Roger Renberg avatar
Roger Renberg avatar
Looking at the "rejection low" map it seems the auto setting rejects most of your pixels leading to the b&w effect. This is rather embarrassing. 
Did you try the with the latest version of the WBPP script too? "Auto" setting never failed on me so far.

Clear skies
Wolfgang

Hello, 


What I did was to use Linear fit clipping instead of Auto. Came out beautifully. Not sure why WBPP does this on Auto? And I have the latest version. Anyway, its now sorted and Im happy  

Here is the same set of data with linear fit clipping together with the slope map (btw, do you have a good answer to what the slope map is used for?) 

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