I've photographed some diamonds/crystals and I want to be able to add some sparkle, not just through a star brush.
I want to get a refraction effect. Ideal it would be a star brush that would 'react' to the colours underneath, or a brush that contained the colors. Not sure how best to explain as I'm new to this side of things.
Where you see the bright white blur/flare I would want to see more colour fringing?
Any suggestions welcome.
You want to see the dispersion effect (rainbows, fire, color flash, etc.).
Yeah, that isn't easy to capture with a digital camera.
I suggest looking at a diamond under a loupe to see how it really displays fire, then mimic that in the photo.
'react' to the colours underneath
Try setting the blend mode on it to screen or multiply.