Lines on pictures

[Saanapix]

Hi!

Since the new update, i have noticed lines appear in raw pictures on all the ones with white/light backgrounds. The lines appear as soon as i try to use a tool to correct the background. The lines move, when zooming in and out, so it’s not my screen making the lines (i have tried this on another computer and the lines also stay there after exporting).

After the line/lines appear, i can’t remove them with any of the tools. This is very frustrating! What can be the reason for this and how can it be solved?

I attached a couple of pictures and a clip.

 

Thanks so much in advance!

[John Rostron]

Hello @Saanapix, and welcome to the forums.

I cannot see any spurious white lines on either of your images. Where are they? I cannot see anything on your .mov file either. It is just 12 seconds of black.

John

[Joachim_L]

I would not call it white lines, but banding.

[Saanapix]

Hi!

 

thank you!

 

Ok. The big question is, how do i get rid of them or make sure they don’t appear anymore?

thanks!

Edited April 28, 2021 by Saanapix

[Joachim_L]

Turn off hardware acceleration in Preferences >> Performance and try if it is better now.

[iconoclast]

Hi Saanapix!

Because you say that "The lines move, when zooming in and out...", I suggest that it could be a sort of interference pattern that results from the difference between the size of the pixels of your screen (screen resolution) and the size of the pixels of the image (image resolution). And even from its alignment. This would mean that these lines doesn't really exist (for example if you print the image out). In that case it would be an optical illusion. But I am not sure about that. Just an idea.

[John Rostron]

A common solution to regular banding issues is the FFT (Fast Fourier Transform) filter.

I applied a FFT filter (Filters > Noise > FFT Denoise) to the image you posted. It reduced the banding to some extent, but not completely. What you actually posted was a photo of the screen, not a true screen capture, so the alignment was not accurate, leading to a Moire pattern. This would have contributed to the interference you report, and also why the FFT filter does not work so well on the downloaded image.

John

[iconoclast]

For a reliable impression of the quality of your image, you should always watch it unrotated with zoom factor 100%, so that the pixels of the image fit to the pixels of your screen.