Banding and fragmentation of color gradients in Illustration

[timeas66581680]

Hi there,
In an old Illustrator CS6 vector, the gradients became banded and fragmented when I opened them in the newer Illustrator. I layered the gradients with the screen blending mode. I used to have no problems with this vector file, but the problem appeared in my new Illustrator (29.1). Can you help me with what the problem could be?

[Bobby Henderson]

Did the AI CS6 artwork have its gradients expanded when opened in AI 29.1? That can be seen pretty obviously if the art is previewed in Outline View. The gradient fill will be a whole bunch of striped lines.

Sometimes when Illustrator artwork is saved down to really early versions gradient fills may be automatically expanded. Some people will save Illustrator artwork to earlier versions in order for the artwork to be opened in other applications.

Another factor that can cause banding in gradients is the fill values of each color stop on the gradient. If there isn't enough variation of colors between the gradient stops banding can occur. For example, a grayscale gradient using only black (K) ink values is more liable to show banding than a grayscale gradient that actually uses all four CMYK inks.

[timeas66581680]

Thanks for the answer. The gradient did not expand when opening. The gradient remained editable. Some gradients had opacity masks, but the problem persists even after expanding them. The gradients go from white to black and from gray to black.
The problem is that I have over 100 vectors that were created in CS6 and contain gradients that I want to work with, but so I have to re-create them all if the banding is not resolved. I use black and white gradients in many places for shadows and lighting effects. When I created these vectors, there was no banding.

[Bobby Henderson]

What kinds of ink formulas do the black to white gradients have? Are they only using a single black ink color or are they using CMYK mixtures for the ink values?

[Ton Frederiks]

Did you check if it is not a GPU preview problem?

Try if switching between GPU and CPU makes a difference: Cmd E (Mac) or Ctrl E (Win).

[timeas66581680]

In both cases, it is banded, only the bands change position as I switch.

[Ton Frederiks]

And previous CC versions did not have that problem? Or did you go from CS6 to 29.1?

[timeas66581680]

There was no such problem there.

[Jacob Bugge]

timeas,

Do you still have the earlier CC version(s), and if you have, what happens if you save in the (latest) viable version and then open that in the newest and then save?

[Ton Frederiks]

I agree with Jacob, you can have multiple versions installed, try opening the files and check them in versions before 29.1. Also check if your hardware has changed, monitor, video card.

If you can, share a problem file here. Save as PDF or rename the .ai extension to .pdf to attach it to a forum post.

[timeas66581680]

Ton,

I'll try the previous versions then, thanks. My monitor changed, but I switched to the right one. I haven't experienced banding to this extent in Photoshop when working with photos, only the usual banding with graphics, which I fix by working in 16-bit instead of 8-bit. This is still new to me with Illustrator, I hope trying the previous versions will help.

[Anubhav M]

Hello @timeas66581680,

I'm sorry to hear about your experience. I hope Ton, Jacob, and Bobby's suggestions helped resolve the problem. If not, kindly share a sample file after uploading it to a file-sharing service so I can check it with the team.

Looking forward to hearing from you.

Anubhav

[timeas66581680]

Jacob,

I tried saving to a new version, but the banding remained. I was able to improve the situation by reducing the number of gradient elements on top of each other, but unfortunately this is not the solution for me.