Live filters and filter layers that stay editable

Apply a blur straight to a photo and the blur is permanent. If you decide later that it's too strong, all you can do is undo or start again. Live filters in Paint by Zaweba keep filters editable, so a choice you made at the start of an edit can still be changed at the end.

There are two ways to use them, both found under Layer > Live Filters.

Filter layers

A filter layer sits in the layer stack like an adjustment layer. It applies a neighbourhood filter, one that looks at surrounding pixels, to everything below it in its group. Blurs belong here, as do Shadows/Highlights, HDR Toning and distortions.

Like other layers it has a mask, an opacity and a blend mode, and its settings stay live. Change the blur radius next week and the picture updates. Paint on the mask to keep the filter off the subject. Lower the opacity to weaken it. Set a blend mode to change how the filtered result combines with what's underneath.

Because it works on everything below it in its group, a filter layer is a natural fit for effects that should cover the whole composition, like a final soft focus or a slight distortion over a finished design. Put it in a group with just a few layers and it affects only those.

Filter stacks under a layer

The second way is to attach filters to a particular layer as a re-editable stack. Each filter in the stack keeps its settings, so you can reopen any of them and change it, or remove one. The stack belongs to that layer and goes wherever the layer goes.

This suits a single element that needs treatment, like a product photo that needs a little sharpening and noise reduction before it's placed in a layout.

The results are cached in tiles. In practice, the app keeps the filtered result in pieces and redraws only what changes, which keeps things responsive as you work.

Jobs live filters suit

Background blur is the obvious one. A filter layer of blur with a mask that hides the subject gives you an adjustable shallow depth of field effect. If you change your mind on the strength, it's a slider.

Shadows/Highlights as a filter layer is handy on photos where you're unsure how far to lift the shadows; you can come back after other edits and fine tune.

Distortions for design work, such as a ripple or warp over a set of layers, are easier to judge when you can revisit the amount.

Getting the order right

A filter layer affects what's below it in its group, so its position matters. Move it up and it covers more; move it down and it covers less. Groups let you contain it. If a filter seems to be affecting a layer it shouldn't, check whether that layer is below it in the same group.

Filter habits to break

Applying filters directly out of habit is the easy one. If there's any chance you'll want to adjust it later, use a live filter instead.

Stacking many heavy filters over a large document asks a lot of your computer even with tile caching. Keep live the filters you still expect to change, and don't pile up ones you've stopped thinking about.

Forgetting about a filter layer near the top of the stack can puzzle you later when everything looks slightly soft. Name or colour tag your filter layers so they're easy to spot.

Live filters are part of why everything in Paint by Zaweba is meant to stay editable. They let you try strong effects without fear, because every setting can be walked back.