Inverting Opacity/Alpha of a Pixel Layer (and How to Use it)

Each pixel has both RGB values and an 'Alpha' (A) value, which sets the transparency (or opacity or alpha) of that pixel. Sometimes when you have a layer (which can be a pixel layer, shape, etc) you might want to invert the transparency/alpha/opacity of the layer. Doing a standard layer invert only changes the colour. Here's a very simple way to do an alpha invert, plus an example (using it as a pixel mask) of how it might be used.

Free resources, including macros, palettes, etc. are here:

If you are a beginner, start here:

[UlfJondelius]

Hi Dave, Missing your videos. Hope you will be back soon!

[nickknight]

Hi Dave, you’ve gone quiet recently, everything ok?

[arvindm]

Hi dave where are you ? Missing you 😢 I love your changingminds website since long

[ezydenias]

Thanks, brilliant, I had the problem of MetallicSmoothnes textures (smoothness was the alpha channel) but Godot using MetallicRoughness, So I needed to Invert the Alpha. Now my Models look as glossy as I intended them to be. Thanks.

[davidhodson]

Looks like a useful technique, I will give it a go.

[chrismartin]

Hi, I use DXO mainly. But I've just downloaded Affinity 2 mainly for photo stacking. Have you got a vlog on this, please?

[MOCT]

Special request. Could you please make a clear, simple video on how to take a signature from a piece of paper and add it to photos? I've just watched four different explanations and still failed. I know you start with a photo of the signature, but after that, everyone does it a different way, and no one explains things clearsly the way you do.

[lazvaldes]

Does anyone know what happened to Dave?

[Dehancer]

Awesome work! We'd like to collaborate, how can we get in touch? :)