Vignetting filter causing banding

Looks like I can reproduce similar effects with the following settings.

  1. No Correction
  2. add DxO Clear View 100%
  3. add micro contrast 100%
  4. add fine contrast 100%

The lines I get change with vignetting settings, but the orientation does not change with it. In some of my tests, the direction of the lines are not circular. See attached examples:


Note: No circular lines… Independent of vign. settings. I can also get the lines in Lightroom.
I suppose that this image just exposes variations due to weather conditions.


Note: No circular lines… Independent of vign. settings. I can also get the lines in Lightroom.
Variations due to weather conditions? Can’t tell.


Check upper left corner - vignetting correction off.


Check upper left corner - vignetting correction on - cannot produce it in Lightroom.

My guess is that the effect is “natural” due to overdoing things.
Raising microcontrast etc. can introduce step effects. I’ve seen an example of it a few years ago but cannot find the source of the demo showing a gradient changing to steps in Photoshop…

Note: Exaples from DPL2, similar in DPL3, both on macOS Mojave

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Thank you for bothering to look at this. While I understand and accept these are extreme conditions and might accept “You should have got the exposure correct in the first place”, one of the great benefits of digital photography (and the dynamic range that modern sensors offer) is being able to recover otherwise unusable shots etc etc. I also accept that processing photos in this way will emphasise any defects present. However, in my case, I have simply enabled vignetting and used ClearView to the max to highlight a problem seemingly introduced by PhotoLab. This problem is still there, although less obviously, at more sensible settings (such as bringing out a bit of interest in an otherwise bland sky). It does appear that PhotoLab is creating this vignetting banding (and I do understand the problem with gradients and banding) where Lightroom/ACR does not.

I would appreciate it greatly if someone at DxO could look at this and see if there’s a solution.

Many thanks.

I note that the OP has turned everything off except vignetting and ClearView. In my experience, Clear View is a relatively extreme correction, even at small settings. I find if I export an image to Photoshop/ACR or to Lightroom after using ClearView, any further work is likely to show up halos. This is especially true if the image is output as TIFF rather than DNG, as a tiff file has all the pixel-level changes “baked in”. While I’m not suggesting that Clearview has definitely caused these subtle circular bands, it would be better for the OP to try outputting the image without using Clearview, if he intends to keep working on it in another software package.

From another thread (about order of corrections), I note that vignetting correction is applied before demosaicing, and Clearview as one of the last after demosaicing. This would be another reason to turn off Clearview for the purposes of testing, so that you just have a basic raw conversion to work on subsequently. Also I would advise not using microcontrast if you intend to process further.

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The banding happens with Auto Vignetting turned on and ClearView off. I used ClearView to highlight the problem. It occurs in all export formats from PhotoLab and I can see it, with only Auto Vignetting on, in PhotoLab. Obviously when going on to edit in another program any sort of increase in microcontrast adjustment only makes the problem worse.

Unless I’ve missed something, this does look like an issue with the Auto Vignetting in PhotoLab.

Hello @stevvi,

Could you, please, provide us with some of the images+sidecars for the investigation? Please, upload them to upload.dxo.com under your forum name instead of “support ticket number” and let me know when ready.

Thank you,
Regards,
Svetlana G.

@sgospodarenko

I’ve uploaded CR3, dop and tif (export to disk from PL)

Many thanks.

Thank you! I’ve sent the data to the ImageProcessing team.

Regards,
Svetlana G.

Hi - just wondering if anyone else has coem across an issue with banding, particularly when processing jpeg files?

No matter what the software, an 8bit file can produce banding because there are simply not enough levels of tonality to represent smooth transitions. A 16bit file can represent 65,536 levels but an 8bit file can only represent 256.

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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Hello LexB
the issue is still open on our side and not fixed yet.