Debayer help

[Ken82]

Im hoping someone on here will have the knowledge to help me out. Ive followed my normal procedure "create master bias, dark and flat then calibrated my lights. Just before i start star alignment i usually debayer but for some reason my image is dark green with no detail when i debayer.  Please see attached calibrated matser frames and raw light frame plus debayered light frame.

Any help would be really appreciated.

Thanks Ken

https://drive.google.com/file/d/19qXMfsyg9nq23eIkCXDDvcA3jVtDDm0G/view?usp=sharing

Masterbias

https://drive.google.com/file/d/1ek5Ji1lmwdmgR2QeFKcmwBZ1vnbrBO7r/view?usp=sharing

Masterdark

https://drive.google.com/file/d/1GLTQ5Qz3NDJari2R4KrOM119wAowIAsQ/view?usp=sharing

Masterflat

https://drive.google.com/file/d/1qEW0_PnPfVcUhzkNxBuWztq_aPLcMkr8/view?usp=sharing

Calibrated light frame (raw)

https://drive.google.com/file/d/1Xrp5jcbNFoiA0jOZkH3aN0XSUmODqRFy/view?usp=sharing

Calibrated, debayered light frame

 

 

 

 

[Tim]

Dont have my laptop to take a look atm, but is the correct debayer pattern selected for your particular camera?

 

[Ken82]

Its a canon 6d so ive selected RGGB. Its always worked well up to this point so im thinking i may have done something?? But then ive tried the same process over and over with the same results.

[MarsG76]

I just convert my RAWs to TIFFS, never gave me any debayering problems.

 

[Ken82]

7 hours ago, MarsG76 said:

I just convert my RAWs to TIFFS, never gave me any debayering problems.

 

When do you normally do that process MarsG76?  Before making master files or before star alignment ? 

Thanks ken 

[steppenwolf]

Can you post up a single subframe with no debayering and no calibration to Google drive?

[MarsG76]

17 minutes ago, Ken82 said:

When do you normally do that process MarsG76?  Before making master files or before star alignment ? 

Thanks ken 

Before any preprocessing... I use cameraRaw in photoshop to convert to TIFF, this way CameraRaw removes most of the noise also.

Once converted to TIFF, the subs only have faint single pixel noise so I run a batch script to remove single pixels, 2 pixel size filter with threshold of 30.

This only removes the noise single pixels and I'm left with a clean sub.

Darks are no longer needed as the light subs are now very noise free.

Flats are treated the same way. Bias doesn't need any treatment past converting to TIFF.

I use Nebulosity 3.3 to stack and assemble all components... before finishing processing in photoshop.

I know that there will be disagreement on no darks needed, but try it, and you'll be surprised I think.

[Ken82]

26 minutes ago, steppenwolf said:

Can you post up a single subframe with no debayering and no calibration to Google drive?

https://drive.google.com/file/d/1BRLQ-2AgKuGdVTmXs_QyWvb-njPDhgMK/view?usp=sharing

[Oddsocks]

Hi Ken.

In your first post with the linked files you have provided a link to a Master Flat however when downloaded from Google Drive it is another copy of the Bias Master so I could not carry out a full calibration in PixInsight.

Just using your uncalibrated single sub in the image calibration tool from the link you provided in your latest post plus the Master Dark and Master Bias from your first post followed by a manual debayer the result looks normal with the Horse head and Flame just visible. The image is green after debayer but that is normal until you carry out a STF stretch with "unchained" channels since there are twice as many green pixels as red or blue.

Looking at your linked image from the first post, Calibrated-Debayered-Light Frame, which contains no stars or data apart from the green colour, and reading the PixInsight history from the FITS header everything looks normal and it should result in a correctly calibrated image, with a green cast of course, until an "unchained" STF stretch is applied. The fact that there is no image data at all suggests possibly a problem with the Master Flat, which you have not provided a valid link for, or, more likely, a rogue frame has slipped into one of the file groups during batch processing, possibly an image file has been added to the flats etc.

I would go back to the raw images and double check that each individual image in the calibration groups only contains Lights, Darks, Flats and Bias with no muddle and run the batch processing script again, hopefully this will resolve the issue, after the rerun, if the image still contains no data but just a green cast then try running the Batch Processing Script without the flats group and see if the data then appears in the calibrated final image.

William.

[Ken82]

55 minutes ago, Oddsocks said:

Hi Ken.

In your first post with the linked files you have provided a link to a Master Flat however when downloaded from Google Drive it is another copy of the Bias Master so I could not carry out a full calibration in PixInsight.

Hi William,

Thanks for your input, i will have a look at your recommendations later this evening. I have edited my original post to include the correct master flat. If this still fails i have also included it below.

https://drive.google.com/file/d/1GLTQ5Qz3NDJari2R4KrOM119wAowIAsQ/view?usp=sharing

Thanks again

Ken

[Oddsocks]

 

Ken.

Attached below is a screen shot of your single frame, calibrated in PI with your Bias, Dark and Flat Masters and then debayered.

Use the settings shown, especially, select the 'Calibrate" check box for the Master Dark otherwise the output image will not be calibrated correctly and most of data will be lost in the resulting image.

There is some shadowing along the bottom of the Flat frame, this translates to appear as a light strip along the bottom of the calibrated image, that needs to be investigated further to determine what caused the shadowing when you took the Flats. There is significant light pollution gradient across the image but that would be removed in your final image using DBE.

The single frame is rather weak as you would expect but you can see the data and correct colour is there.

HTH.

William.

 

[Ken82]

Thanks William it appears I have resolved the issue. It may have been the calibrate as you have mentioned or something else I never clicked . 

Cheers ken