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+--- Thread: Correction of rainbow effect and/or Moiré effect? (/Thread-Correction-of-rainbow-effect-and-or-Moir%C3%A9-effect)
Correction of rainbow effect and/or Moiré effect? - eremit - 12-02-2018
Hello!
So, I have this two images:
https://flic.kr/p/2dj483V
https://flic.kr/p/2dj2XoX
The first one has those diagonal lines all over the place, and the second has that rainbow effect, more notorius on the mountain but it's all over the image.
I've applied the Descreen plugin on the first one, for it seemed to be a Moiré effect, but, besides removing some other patterns, had almost no effect on the lines themselves. Tried removing the "stars" on the Fourier filter, to the almost exact same result.
As for the rainbow effect on the other one, I have no idea of what it could be, and I couldn't find any techniques for removing it, so here I am, asking for help for both those images.
The first one is in 600ppp, second one in 300ppp.
Thanks!
RE: Correction of rainbow effect and/or Moiré effect? - Ofnuts - 12-02-2018
IMHO the diagonals in the first have been put in it on purpose.
In the second one the rainbow is a likely moiré effect. One way to mitigate it:
- add a transparent layer, set to Saturation mode (towards the bottom of the list)
- paint on in white over the areas where the rainbow is the most visible (mountain, lighthouse)
- this will lighten the area a bit, you can adjust the opacity of that layer (the more transparent, the close you are to the initial picture, but at around 50% you don't lighten much and the rainbow is hardly noticeable
[attachment=2345]
RE: Correction of rainbow effect and/or Moiré effect? - eremit - 12-03-2018
Thank you a lot!! I wil do that.
On the other image, the lines are definitely a side effect of the scan; they are all plane colors on the original (it's a paper collage), so any help on that would be great
