Why is my brush looking pixelated & dithered over transparent background?

Forum|Forum|4 years ago
October 6, 2021
5 replies
4093 views

This just started happening an hour ago and I'm pretty sure I must have done something to cause it, but for the life of me can't figure out how I did it. Can't seem to find a problem like this online either, all of them are usually solved by switching to the correct brush / changing blending mode.

Here's the gist: when drawing with a soft brush, or erasing with a soft eraser over a transparent background, the color appears to be distorted and edges pixelated. It looks just fine over a background, though.

Screenshot of the effect:

Video can be seen here.

Things I have tried: updated the drivers, checked & unchecked GPU acceleration, all to no avail, the issue persists. The files display fine in other programs, so it must be some view issue in Photoshop itself.

All help is greatly appreciated.

Windows

This topic has been closed for replies.

Correct answer davescm

It is just a preview rendering artifact, and has been that way for years. It does not affect your actual image.

Put a temporary solid layer at the bottom of the layer stack then remove it, or turn off visibility, before exporting/saving.

Dave

C

Codie

Participating Frequently

Found a potential workaround — in my case, the source images had been exported as PNG renders from 3D software. I was getting the dithering when I tried to use layer masks. I simply copied the source PNGs and pasted them into a fresh PSD document and it fixed my issue. I think the first attempt was beholden to the color indexing of the PNG file (not the full gamut available).

K

Kinga5ECE

Participating Frequently

any solution found? I think I tried everything

creightonc97915457

Participant

I've got the same issue and can't work like this. I'm drawing with a soft brush or using the gradient too and the (what should be) transpearent pixel is showing up at high contrast and dithered. It's probably that the monitor is having difficult time replicating the super suble color difference, but this has never been a problem before on default. I believe I've just done and update also.

D Fosse

Community Expert

This has to do with blend gamma - the transparency "curve" from fully opaque to fully transparent.

There is a checkbox in Color Settings to "blend RGB using gamma x.x", and if you check this (default value 1.0), you get the same appearance whther transparent or white background. Unfortunately, you then get the "bad" appearance in both cases.

Photoshop uses a custom blend gamma value that will most closely correspond to how ink behaves on paper. I think it's somewhere around 1.5.

I don't know enough about the technical background here, but apparently blend gamma only applies when there is actually something to blend with - either a background color or an underlying layer.

In other words, I don't think there's an easy way around this.