Bloom possible with transparency? (CYCLES)

Support Compositing and Post Processing
1

Anyone here use the Bloom node setup to create glow? It’s done in the Compositor, rendering with Cycles.
Problem: I am unable to achieve the glow when I check Transparency (Film menu under Render Settings)

Additional question: Is it possible to enable/disable transparency as an option on individual Render Layers?

I’ve attached a blend file showing the Bloom node setupbloom_cube.blend (541.9 KB)

Screenshot_bloom_cube
Screenshot_bloom_cube.png1280×1024 296 KB

2

There are lots and lots of threads here showing you how to do this. Bloom doesn’t work because it doesn’t affect the alpha channel that transparency creates.

3

Actually the bloom is still there and it works over transparent areas also. The alpha channel makes it invisible, but if you alpha_over with a background, the bloom can be seen…
This is very similar to rendering volumetric materials in Cycles.

4

Thank you Secrop! It was such a simple solution to composite it over an image!

5

image
image1920×1080 439 KB

6

thanks yogyog,
trying this myself right now and not getting as much intensity as you are…
will keep trying
maybe theres adjustments I have to make to the area light