Operating system: Windows-10-10.0.17134 64 Bits
Graphics card: GeForce GTX 1060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 419.17
Broken: version: 2.80 (sub 54), branch: master, commit date: 2019-04-06 12:26, hash: rBcc73d59ad580
Short description of error
Eevee Bloom effect exhibits noticeable banding that does not appear to be affected by image bit depth or any setting.
Exact steps for others to reproduce the error
Any bright emission object with bloom enabled shows banding in the bloom.
Maybe this is just a side effect of how the bloom works, but I could not find an answer anywhere (manual, Maniphest, google), so here we are :)
Original report by a user showing example output in:
Simple blend file attached (open, hit F12)
I played around with every setting without seeing anything affect it. I exported Eevee renders in 16-bit and float formats and still saw it.