I’m rendering a series of images with a solid colour background. I usually composite in Photoshop, but I’m trying to do it in Blender to save some time.
When I render in Blender with transparent film, I can composite in PS with no problems. When I use the alpha-over to get a white background, fine detail disappears and I get harsh edges to the model’s alpha.
There should be a simple node set-up to get around this, but I’ve had a Google and couldn’t find anything specific to fix the problem.
Here is my node setup in the compositor. I’m rendering with an HDRI, so I can’t set the background colour.
First off, why are you premultiplying again in AlphaOver node (the checkbox)? If you render with transparency, image is already premulted. Second, change the bg color to something darker and see if wires are there. On bright bg bright wires might not be visible. Theremight be something else funky, better upload an example still or blend file if you can’t sort it out.
To rephrase what JA12 wrote, you don’t have alpha in your renderlayer, so you can’t do an alphaover. What does that renderlayer look like to start with? Why do you want to over it with white if it already has white bg?
Render with transparent film as you did for PS and do an alphaover with white. What does that look like?
As others have written, it might just be light coloured spokes blending into the white background. Have you tried lighting your model differently? A back-lit effect might bring the detail out.
