Brush Settings: Colour Dynamics
In photoshop, you have the option to paint each mark with a new tint of colour. This is via the Colour dynamics option.
You can acess this option, when you go to your brush settings. And under your current selected brush chosen > it will have various options such as size, opacity, jitter, blah blah.
Colour Dynamics: Options and Fine Tuning Summary
By setting your foreground and background to different tones of colour or value, your modified brush can be set to paint like an oil brush (seen in painter)
- FG/BG jitter: 80-90% - tells the brush to alternate between the FG/BG
- Options: Fade 50-70% - determines the duration/transition between FG/BG
- Hue/Brightness: 2-5% - provides slight variance in colour and hue/brightenss change from your original colour (mimic traditional brushes)
- Saturation: 0% produces pastel effect. > 1% produces a saturated feel
- Purity - 0% (ensures your original colour is used). 1%

This works best with a custom brush made of horizontal strokes when producing your custom brush

A similar detailed outline on how to produce a custom oil brush can be found at this link
Hope that helps a bit
NB: Please experiment and post your results. Only through experimentation will you (hopefully continue the spirit of sharing as I have done here) pioneer and keep on sharing/growing in the arts.
CAUTION: Could I please advise some caution in the sense that less is more
- Dual brush settings (can slow painting experience esp at large sizes > 500 pixels)
- Any increase above 5% causes too much alteration of colour, hue, saturation. I would advise extreme subtlety. As only subtle changes, will be required to mimic a oil like brush.
- Might be easier to just use Corel painter. (but if set up right , your brush can do wonders)
- This kind of "oil painting brush" is best used initially, when laying out rough forms during the initial composition. Afterwhich, a hard brush is prefered.
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