How to add film grain to a photo
Paint by Zaweba adds film grain three ways: the Photo Grain filter, an editable Grain Layer you can change later, or the one-click Film grain look.
There are three ways to add grain in Paint by Zaweba, depending on how much control you want. Filter > Noise > Photo Grain adds grain straight to a layer. Layer > New Grain Layer adds it as an editable smart filter, so you can change it later. And the Film grain look in Quick Looks does it in one click with an intensity slider.
Grain does more than make a picture look old. A little of it hides banding in smooth skies, makes a heavily edited photo look more natural, and ties together a picture built from different sources. The trick is choosing the right amount for the size the picture will be seen at.
Grain versus noise
Digital noise is what a camera sensor produces in low light: coloured speckles, often blotchy. Film grain is finer and more even, usually without the colour. They look different, which is why a Photo Grain filter exists alongside Add Noise. Paint by Zaweba's Noise menu has both, along with Reduce Noise, Despeckle, Dust and Scratches and more, but for a film look, Photo Grain or a Grain Layer is the place to start.
The editable way
Choose Layer > New Grain Layer. The grain is added as a smart filter, so it stays editable. You can open it again and change the amount or character at any time, hide it to compare, or mask it so some areas get less grain.
This is the best route if the picture might be reused at different sizes. Grain that looks right on a big print can look like dirt on a small phone screen, and an editable layer lets you tune it for each version.
The direct way
Filter > Noise > Photo Grain adds grain to the current layer. It's quick and simple. If you use it, run it on a copy of the layer so you can lower that layer's opacity or delete it later. That gives you most of the flexibility of the editable route.
The one-click way
Open Quick Looks from View > Panels or Image > Quick Looks and pick Film grain. Hover over a look to preview it, then use the intensity slider to set the strength. You can apply it to the current layer, the whole image or a selection, and optionally keep it editable. Quick Looks also has looks like Faded film, Old photo and Light leak, which pair well with grain for a full analogue feel.
Getting a good result
Add grain last, after resizing. If you add grain and then shrink the picture, the grain is averaged away. If you add it and then enlarge, the grain grows into blobs.
View at 100 percent and at the size people will see it. Grain judged when zoomed in tends to be too strong when viewed whole, and the reverse is true for small previews.
Keep grain even across the picture. Grain that's strong on the subject but missing in a pasted sky gives a composite away. That's exactly the case where adding a single grain layer over everything helps, because it unifies the parts.
Use less than you think. A subtle grain that people feel rather than notice usually looks best, especially on portraits.
Pairing grain with other looks
Grain is part of a look rather than a look by itself. Soft contrast, slightly lifted blacks and gentle colour shifts all help it read as film. In Paint by Zaweba you can build that with adjustment layers below the grain, or start from one of the Quick Looks and add a Grain Layer on top. Save the combination as your own look and it becomes one click next time.
