Building your own filters with Filter Graph in Paint by Zaweba
Filter Graph in Paint by Zaweba wires filters, colours and blend nodes into custom filters and textures you can save as presets and run in batches.
Many looks you like are really a recipe of several filters: a blur here, a colour change there, a texture blended on top. Doing that by hand every time is slow and hard to repeat exactly. Filter > Other > Filter Graph in Paint by Zaweba lets you build the recipe once as a set of connected nodes, then save it and use it again.
How the graph works
A graph starts with the layer as its source. From there you add nodes. A node can be any of Paint's filters, including filters added by plugins, a flat colour, or a blend node. You drag nodes around the canvas and wire one node's output into another's input, so the picture flows through the chain from source to result.
Blend nodes are what make a graph more than a list. A blend node takes two inputs and combines them with a blend mode and an opacity, and it can take an optional mask that controls where the blend happens. That means you can split the picture, process two copies in different ways, and bring them back together, exactly as you would with duplicate layers and blend modes, but in one reusable filter.
Loops are refused. The graph has to flow one way, so you cannot wire a node's output back into something earlier in the chain.
A simple example
Say you want a soft dreamy glow you can apply to any portrait. Start from the source. Run one branch into a strong blur. Blend the blurred branch back over the source with a lightening blend mode at modest opacity. Add a flat warm colour and blend it over the result at low opacity for a gentle tint. Wire the last node to the output, and you have a glow filter you can save.
Textures from nothing
Because flat colours count as a source of their own, you can also build textures that do not depend much on the layer. Combine render filters, noise and blends to make stone, fabric or abstract backgrounds, and save them as presets for later.
Presets, actions and batches
A finished graph saves as a preset. That keeps your look exactly the same across a set of photos.
Graphs also run inside actions and batches. Record an action that resizes a photo, applies your graph and saves, then run it as a batch over a folder of pictures. The whole folder gets the same look without you touching each file. Graphs run in 8-bit, so for 16 or 32-bit documents expect the result to be converted for that step.
Good results with graphs
Build in small steps and check the preview as you add each node. If the result goes wrong, it is far easier to see which node caused it when you have only added one since the last good result.
Keep strengths moderate inside the graph. A filter that looks right on one photo can be too strong on another, so a chain of gentle steps travels better across a batch than a single heavy one.
Name and organise your presets. A short descriptive name, such as warm glow or film fade, helps when you have built a dozen of them.
Mistakes to avoid with graphs
Wiring a node but forgetting to connect it to the output leaves it with no effect; follow the wires from source to result if a node seems to do nothing. Running a graph built for colour photos on black-and-white ones can give odd results, so make separate presets for different kinds of picture. And if you rely on a plugin filter in a graph, keep that plugin installed, or the graph has nothing to run.
Filter Graph turns the large filter menu in Paint by Zaweba into building blocks, which is where many custom looks and house styles come from.
