BTW - it also looks like the op was getting this using RAW files…
Thanks. This is really bad banding, though. Results in unusable images.I can’t repeat this in any other processing software. If there was a problem with my jpegs, that would show up at least a little bit elsewhere. It absolutely does not. LR, Photoshop, Gimp, Exposure, ON1, Rawtherapee tried so far.
TBH, I have come to the conclusion PL3 is not for me. I realised the problem occurs on import, after turning off all corrections and tools in Photolab. Looking carefully, the banding was still present. It seems the import process or file handling is responsible, so it looks like there is no way to avoid the issue.
Thanks
Can you make available one of the images having the issue?
I use Photolab as my main RAW converter and I’m happy with it.
But recently I’ve started with astrophotography and noticed that Photolab isn’t working properly. The raw conversion is causing weird concentric circles in the astro photo’s. Post processing astro photo’s is difficult because of the lack of light, the peak of the histogram is mostly around 1/4.
Knowing the difficulties in post processing astro photo’s I’ve searched the internet for possible reasons. I found a post on Cloudy Nights that using lossy compression with RAW for Nikon can cause this effect: Nikon Coloured Concentric Rings - DSLR, Mirrorless & General-Purpose Digital Camera DSO Imaging - Cloudy Nights . But I’m using a Nikon D7200 with 14 bit losless compression, so this is not the reason for these weird concentric circles in my images. And using other RAW converters (Nikon Capture NX-D, Rawtherapee and Affinty Photo) showed that this effect is almost absent.
But I think I’ve found the reason for these circles, it’s the vignette correction in Photolab. Without the auto vignette correction these circles don’t appear. To show the effect I’ve made a photo with the histogram peak around 1/4 from the left.
Converted the RAW file with Photolab using the preset ‘no correction’ and then only applied the camera and lens corrections (and vignette correction on) with the prime noise reduction. Saved this as a 16 bit TIF file and the processed this TIF file in Affinity Photo using the same techniques for astro, i.e. stretching the histogram with levels and/or curves. Doing this will show the artifacts introduced by the vignette correction of Photolab:
Not using the vignette correction of Photolab, the concentric circles don’t show up. And converting the RAW file with Nikon Capture NX-D, Affinity Photo or Rawtherapee with vignette correction on, there are no concentric circels. As a new user I’m not allowed to upload these photo’s.
Now I’ve found this topic and see that this problem is already reported in december 2019 for Photolab 3. Unfortunatly this problem hasn’t been solved and still exists in Photolab 4.
Any feedback from DXO would be appreciated.
Many thanks.
Good day @LexB,
Could you, please, provide us with this RAW file (and a sidecar if available) for the investigation? Please, upload it on upload.dxo.com with your forum name in ‘support ticket number’ field and let me know when ready?
Thank you
Regards,
Svetlana G.
Hello Svetlana,
I’ve uploaded the RAW file and the sidecar. Also the TIF file generated by Photolab and the processing of this TIF file in Affinity Photo using levels and curves for stretching the histogram.
Kind regards,
Lex
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Good morning Lex,
I’ve got them, thank you. We will investigate the issue.
Regards,
Svetlana G.
Hello Svetlana,
Could you please give a status update on this issue?
Is the cause already known and when will it be solved (update june 2021?)?
Kind regards,
Lex
Good morning @LexB ,
Well, the issue (id = DFRMWK-17944) is in the backlog but I can’t say anything about the timeframe as it’s not an easy one to fix. I will let you know as soon as it’s fixed.
Regards,
Svetlana G.
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Can you tell me if this issue is fixed/solved in PL6?
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