Lucky Clan Forum

Support => Suggestions, Ideas, Bugs => Topic started by: GabrielaShelArts on September 29, 2021, 09:32:05 AM

Title: Color Banding issue (gradients)
Post by: GabrielaShelArts on September 29, 2021, 09:32:05 AM
Hey guys!
While working on a commission I realized, that I'm having a problem with color banding. I saw it when I exported it to a bigger screen, but it's also visible on the ipad. It's mostly present in the dark blue tones. I tried using different brushes but can't get rid of it. I played around with different color profiles, but that doesn't seem to be the issue. Is it ipad related?
I work mostly with the Digital Round brush in the Digital Painting brushes.
See the issue in the attached screenshot.
File size is A3, 300 dpi. Ipad Pro 12', 2018.
Any idea how I can prevent that? It's work for a client, and I'm afraid it won't be accepted that way for printing.
Title: Re: Color Banding issue (gradients)
Post by: lastaccess on September 29, 2021, 10:14:26 AM
Noisy airbrush can soften these gradients pretty well.
Title: Re: Color Banding issue (gradients)
Post by: Andreas Raninger on September 29, 2021, 11:33:13 AM
Another way is to add an overlay layer, fill it with 50% gray, add noise filter and adjust until the banding go away. Do the final touch by adding guassian blur and adjust. Paintover the area that do not band with 50% gray or just erase with a soft airbrush. I do this sometimes and then use the unsharp sharp mask to enhance details. Go as high in resolution as you can when doing this.
Title: Re: Color Banding issue (gradients)
Post by: icezimy on September 29, 2021, 03:20:13 PM
Color banding is generally a thing that happens with digitalart, mostly when painting large gradients without texture especially with the round brush or airbrush.

An easy way to fix it is to duplicate the layer or to select affected area and „add layer via copy“. Then add surface blur to it until most of the banding dissapears. Then you can add a mask, paint with black, to remove it from areas you don't want the blur, and then if needed, add a new layer to paint back in any details that might have been lost.

Another/additional way already mentioned is to add a new layer on top, fill with 50% grey, set to overlay, and add noise until banding mostly dissapears, then add mask again to remove from unwanted areas, and adjust layer opacity if needed.

Next way is to add any grey textured layer on top, set to overlay and adjust opacity, erase, adjust or add mask as needed.

Final and most time consuming way is to paint over affected area with smaller or more texture brushes.

And to generally prevent it from happening again, you can either avoid painting gradients with very large brushes, and paint in with smaller strokes instead, or use more textured brushes.

Hope that helps :)
Title: Re: Color Banding issue (gradients)
Post by: Andreas Raninger on September 30, 2021, 03:19:16 AM
Has someone tested if the banding is visible when printing the image? I can't remember that I had any banding in the final print. Could it be that our displays shows banding but the print don't and displays can't show all of the colors like in a gradient. Trying to fix banding might also lower the quality of the final product if it's going to be printed. I get banding in 16-bit Photoshop projects on my computer, but the the big advantage working in 16-bit is that adjustments will not destroy image color quality. I tested on my professional display and there is no banding on that display. So I might be right about that the display having problems showing the all the colors when using smoth transition like in a gradient or using an airbrush. Artstudio is using 64-bit when it operates on our layers so you shouldn't be worried about the banding. The final product when printing will not show the banding if printing in high quality. The above methods can be used when creating images that will only be used on a consumer display like when published on the internet.
Title: Re: Color Banding issue (gradients)
Post by: icezimy on September 30, 2021, 08:54:49 AM
Usually if you can already see the banding on your screen, it will be even more obvious when printing
Title: Re: Color Banding issue (gradients)
Post by: Andreas Raninger on September 30, 2021, 11:28:41 AM
You are right when working in 8-bit but printing 16-bit images to my Samsung laser I get no banding. I tried ASP printing and got banding. I got banding in 16-bit on my consumer displays but not in my pro display. No trace of banding on my 8-bit book covers of what I have seen.  :-\
Title: Re: Color Banding issue (gradients)
Post by: Andreas Raninger on September 30, 2021, 11:36:16 AM
I found this page when searching. Make things clearer when it comes to printing the final product.
https://www.primoprint.com/blog/the-difference-between-8-bit-and-16-bit-images-and-how-to-utilize-each/ (https://www.primoprint.com/blog/the-difference-between-8-bit-and-16-bit-images-and-how-to-utilize-each/)
Title: Re: Color Banding issue (gradients)
Post by: Lucky Clan on October 06, 2021, 07:01:56 AM
There will be one more option to improve the banding a bit in version 3.3.
It will use Brush Editor > General > Noise value in Wet Paint / Smudge tools. Now these tools ignore the "Noise" option, it use used only in Paint tool.

And in a more distant future we will add 16-bit format support. Today 16-bit processing is used only when painting a stroke, and after the stroke is ready it is added to 8-bit layer content.