Banding sucks. When I first started playing around in photoshop, I would have no idea how to solve obvious banding problems whenever I was working with gradients. Fortunately it’s an easy problem to solve – just add noise!
Sounds simple enough, but you’ll have to be careful not to go overboard as noise can just straight up ruin your image. Here is safe way to add noise that isn’t destructive which will easily allow you to tweak settings if you feel like it later.
Here is a gradient I was having problems with yesterday. You’ll find the banding more noticeable when you have similar colors in a 2 color gradient, and the distance between the two is relatively far.
Lets start off by converting the gradient to a smart object by right clicking on the layer.
Then lets add some noise to the smart object by selecting Filter > Noise > Add Noise
Now the goal is to make this as subtle as possible, so lets only add 1%.
Looks like the banding is gone, but even at 1%, the image looks way too noisy. Since we added the noise on top of a smart object, we can easily modify attributes of the noise on the fly including the amount, and transparency. Since we already have the lowest amount of noise available, we’re going to reduce the transparency to make it a bit more subtle. If you look in the layers palette, you’ll now notice a little levels icon underneath our smart filter.
Double clicking that will allow us to edit the transparency of that smart filter alone. At this point you’re going to want to knock back the opacity to a nice middleground where the noise isn’t obvious, and the banding is gone. In this case, I’ll set it to 50%.
If you’re experiencing banding when you’re saving or compressing your images, another solution is to add noise to the channel where the banding is most prominent. There are a couple extra steps involved, but the end result is much more subtle and worthwhile.