Do you have a tutorial on how to use the shadow and highlight blending mode? For instance what colour do I use for shading? Is it best to use grey? I'm going to try it out on skin colours. c:
Here’s a sneaky tip: Shadow, Tint and Highlight are actually just Darken, Multiply and Screen.
Waaaay back in ArtRage 2, and also now in ArtRage Lite, those were the only blend modes, renamed to be more accessible to users who have never heard of Photoshop blend modes. The full version has the entire range, but we leave those three up the top as shortcuts/so people can actually keep using the ones they’re familiar with.
This means that any good tutorial on Photoshop blend modes will tell you exactly what you can do with these ones.
But here’s the basic intro ;D
Shadow, Tint and Highlight
Set a layer to use a blend mode in the layers menu.
Once active, you can click the blend mode symbol to quickly access the list of blend modes. Tint, Shadow and Highlight have unique icons (T, - and +), the rest just use ‘…’
Darken (Shadow) makes stuff darker. It basically takes the previous colour and the new colour and adds them together to give you a darker combination of both colours.
Darken is good for consistent shadows and for… more realistic lighting. So red light on blue will create dark purple because there’s a red ‘shadow’ over the purple background.
Multiply (Tint) makes stuff more of whatever it already is - it multiplies the effect. So if you add dark colour to dark, it gets darker. Add light to light, it gets lighter (this is why it’s used to vanish white backgrounds).
Multiply is good for shadows where you don’t want to accidentally shade over various lighter bits and for, well, deepening the effect. It will keep the overlay colour, so it’s more like you’re tinting the original with a new colour.
Screen (Highlight) makes stuff lighter, the opposite of Darken. So use this one for consistent lightening.
To answer your actual question:
Use the colour you want to emphasise. You’re not just making stuff darker, you’re adding colour - and the end result of that is going to depend on both the base colour and the new, blend mode, colour.
This is the difference between adding a low opacity layer of shadow and a blend mode - blend modes interact. Multiply is halfway between no blend mode and ‘Darken’.
No blend mode: Even layer of new colour over everything
Tint (Multiply): Some new colour added to the old colour softly over everything
Shadow (Darken): New colour mixed with old colour to get a darker and more intense combination of both
So I wouldn’t use grey - it will just make things greyer. In most cases, just use the same colour you used for the base layer. If it doesn’t look quite right, use a greyer (less saturated) version, or adjust the layer opacity.
Here’s some further reading on blend modes:
The ArtRage manual ;D https://www.artrage.com/manuals/artrage-4/layers/
Layer Blending Modes in Photoshop and Elements: a quick overview of all the possible blend modes http://www.northlite.net/ps/blend.htm
A more comprehensive overview based on ArtRage 3 (PDF) https://forums.artrage.com/files/layer-blend-modes.pdf
A video intro to the blend modes in ArtRage 4: https://www.youtube.com/watch?v=xETiycVkhJo