Want Better Gradients On Press? Here’s The Tip
If you're designing a job that will ultimately go to a printing press in CMYK mode and it's going to contain one or more gradients, you'll get better printed results (less color shifts) if you create those gradients after you convert to CMYK mode.
You can also add a very slight amount of noise to give the gradient some “tooth”. I almost always do gradients in PS instead of vector apps. Especially if you are going from really dark to really light. You might also talk to your printer about the curves they use on their press. Many printers have gone to a higher contrast curve to meet customer demands for “punchier” photos and graphics. This curve results in banded gradients due to decreased dynamic range. On a job a few years back, I had a printer use their old press curve and it fixed the banding problems we were having.