No color in DSLR su...
 
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No color in DSLR subs  

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(@testclaim5250)
White Dwarf Customer
Joined: 1 year ago
Posts: 12
January 13, 2019 22:24  

Downloaded the latest version today and started the trial.  I hear this is a much better program that deepsky stacker.  I have watched several videos, read several posts, but can't seem to find my answer.  In my setup I have Bayer CFA pattern set to RGGB and I have tried supported.  I have algorithm set to no interpolation.  Every single time I go through all my images are black and white.  These were all 5 minute subs taken with a Canon t6i no modifications.  I have to assume I'm missing a step or a setting somewhere.  Can someone point me in a right direction?

Thanks!!

Eric 


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(@testclaim5250)
White Dwarf Customer
Joined: 1 year ago
Posts: 12
January 13, 2019 22:25  

One other quick note I forgot to put in.  The final integration appears to have a very strong gradient that I don't see in Nebulosity or DeepSky Stacker.  Another setting I missed?

Thanks


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(@vincent-mod)
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Joined: 3 years ago
Posts: 1117
January 13, 2019 22:48  

First of all, it indeed is far better calibration-wise and such. 🙂 The gradient in the end must be in your data, DSS probably did a different stretch in the end which makes it less obvious. Gradients can be removed by using flats and the light-pollution correction in the "tools tab" on the end result.

So for everything being gray.. you might try the option to force CFA in the first tab (0) and if you're sure about the pattern, select it to be RGGB.


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(@testclaim5250)
White Dwarf Customer
Joined: 1 year ago
Posts: 12
January 13, 2019 23:15  

Thank you.  Force is the last option I tried with the same result.  I have tried specifying RGGB and no interpolation.  Same results.  I should mention these are raw FITS files versus the standard cr2


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(@vincent-mod)
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Joined: 3 years ago
Posts: 1117
January 13, 2019 23:57  

Ahhh so did you use another program to get those FITS files? I think that's the problem, try it with the .cr2 files, it's always the best anyway.


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(@testclaim5250)
White Dwarf Customer
Joined: 1 year ago
Posts: 12
January 14, 2019 00:00  

Yes, my capture program is Sequence Generator Pro.  Thank you.  I will try cr2 but that will take some time.  I have to wait for clear skies 🙂 🙂  then get all my calibration frames again.  they are all in fits too.

Just curious.  Why is cr2 best?  Everyone keeps saying fits is, but never a real explanation.  


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(@vincent-mod)
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Joined: 3 years ago
Posts: 1117
January 14, 2019 00:12  

FITS is a fine format to end up with, but using the "purest" raw file straight from the camera is the best starting-point. Then let APP use that to create the FITS files, as no in-between step will then have introduced a potential problem or did anything else that might have been negative, like what I think is the case here. My guess is that in SGP there is some setting set wrong to convert to FITS.


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(@testclaim5250)
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Joined: 1 year ago
Posts: 12
January 14, 2019 00:15  

Ok.  Next time I'm out, I will start getting with cr2.  thank you for that!!


(@mabula-admin)
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Joined: 3 years ago
Posts: 2200
January 17, 2019 13:19  

Hi Eric @testclaim5250 & Vincent @vincent-mod,

Let me first respond to the initial question:

"Downloaded the latest version today and started the trial. I hear this is a much better program that deepsky stacker. I have watched several videos, read several posts, but can't seem to find my answer. In my setup I have Bayer CFA pattern set to RGGB and I have tried supported. I have algorithm set to no interpolation. Every single time I go through all my images are black and white. These were all 5 minute subs taken with a Canon t6i no modifications. I have to assume I'm missing a step or a setting somewhere. Can someone point me in a right direction?"

Yes, there is a very good explanation why the color is not there in this case. It will happen with both FITS and CR2 frames if you set the CFA algortihm to No Interpolation.

By setting it to No Interpolation, you tell APP to NOT Debayer the data, but you need to debayer it to get color 😉

The No Interpolation setting is for data shot with a debayered DSLR, a DSLR where the Color Filter Array has been removed from the sensor. Therefore, if you set de algorithm to No Interpolation, 2 things will happen:

  1. the data won't be debayered
  2. the data will be shown monochrome instead of  3-channel RGB.

 

So for you purpose, it's best to leave the Bayer CFA algorithm on the default of Adaptive Airy Disc 😉

 

Now, if you use CR2 data, you will have 2 advantages over FITS data acquired with SGP:

  1. the CR2 will be still completely raw in 14bit (most current models are 14bit) and APP will use the original raw data
  2. APP will automatically know how to interpret the CR2 frames, it will know the correct Bayer Pattern. SO in the menu 0) Raw/FITS you won't need to change anything.

 

I am not saying that FITS frames from SGP are inferior, they do contain all data 😉 only converted already to 16bits, but it requires you to set some settings in 0) RAW/FITS for proper data interpretation.

SGP will give you FITS frames without meta data to indicate which Bayer Pattern the sensor has. So, to start with, APP would not know if it is Bayer CFA data and if so, what the correct Bayer Pattern would be.

So for your FITS frames you will need to set the following settings for correct processing with color:

  • first enable Force Bayer CFA, this tells APP that the data is from a Bayer CFA sensor and needs to be debayered.
  • leave the Bayer algortihm on the default of Adaptive Airy Disc, don't set it on No Interpolation !
  • Set the correct Bayer CFA Pattern for you sensor.

 

Then your images will be properly processed and they will show color 😉

So either CR2 or FITS from SGP are fine, but CR2 is easier.

Please let me know if you can now process your fits frames correctly 😉

Kind regards,

Mabula

This post was modified 1 year ago 4 times by Mabula Haverkamp - Admin

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@testclaim5250)
White Dwarf Customer
Joined: 1 year ago
Posts: 12
January 19, 2019 15:59  

I made the adjustments as suggested and I now have color!!

Thank you both.  In the future I will deal with CR2.


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(@mabula-admin)
Quasar Admin
Joined: 3 years ago
Posts: 2200
January 19, 2019 20:22  

@testclaim5250, excellent 😉 thanks for the feedback !

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


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