Raw conversion challenge: moire

I have a camera which can sometimes produce quite a lot of moire (Nikon Coolpix A: 16MP, no AA filter, very sharp lens). The colour aspect of moire is relatively easy to remove but the remaining luminance pattern is not.

I’d like to see what methods others use to tackle moire in PhotoLab. Here’s a raw file for you to play with.

It’s a shot of a resolution test chart which I downloaded and printed on a BW laser printer.

Here’s my best attempt at processing the file in PL2:

And here’s what I can do with it in Lr5:


Not perfect, but I prefer the latter result. It’s easier to auto-mask the chart in Lr and there’s the moire removal option with local adjustments (unlike in PhotoLab2). I should also add that I tried the file with Lr Classic Enhance Details demosaicing option and it gives me the best outcome before I start playing around with local adjustments.

I’ve disabled the distortion and vignetting corrections in both raw converters on purpose, so I’d like you to do that in your attempts as well, so that we can have more or less similar general processing. Thank you.

The Elite Edition comes with a Anti-Morie Tool.

That’s how I handle it. You didn’t tell us what version of PL you have.

See Fine Tuning and Lens Correction Geometry In Help

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Yes, I sometimes use it at smaller values if the moire is rather faint, but the problem is that it’s a global adjustment. Moire frequently occurs when shooting portraits when there’s fabrics in the frame – a global moire removal in PhotoLab desaturates lips and eyes in an unacceptable way. Also, it only takes care of the colour aspect and leaves the luma pattern behind.

I used PL 2.3 Elite.

In my OP I decided to switch off the moire module because it made the luma pattern worse and I tackled the problem only with a local adjustment. Here’s what the image looks like when default NR and moire removal is applied (no local adjustments):

Here’s my take on it using local adjustments.

Mark

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Very nice, better than my versions. I think I see what you did – you pushed the Blacks slider all the way down in local adjustments, didn’t you?

Yes, but the black slider wasn’t enough. I also pulled the exposure slider all the way down and just painted over the solid black areas with the automask. Then I painted the entire chart with a new mask and desaturated it all the way to remove the color artifacts. It’s cheating, I know, since it really doesn’t address moire removal, My image is lighter than yours. I inadvertently left the image set with the DXO Standard preset rather than a No Correction preset, but for the purposes of this exercise it really didn’t matter

Mark

I need to learn how to use automasking in PhotoLab because it wasn’t working the way I expected and I just used a regular brush. It was somewhat tedious when compared with a 5 seconds automasking I did in Lr.

In a way this image is not the worse case scenario because the subject affected by moire is black and white, so desaturation does work. But if it’s a blue-striped shirt then I don’t see a convincing way of editing it in PhotoLab alone.

I did say it was cheating, made possible by your choice of the subject.

Mark

It’s interesting that in Lightroom I used a maxed out positive Tint correction which helped a lot in fazing out the luma pattern left over after desaturation. It didn’t work too well with PL because of my very crude mask.

Anyway, thanks for playing. I learnt something new from your post.

OK, playing more with automask in PL – what threw me off of it was the mask preview it generated; I expected it would work like in Lr (when you release the brush stroke the mask preview gets updated to reflect the refined area, which doesn’t happen in PL2).

Anyway – I can see two ways to achieve the same fazed out result with a local adjustment: either desaturate/full reduce Temp/full enhance Tint, or fully reduce either Shadows or Blacks.