Yep, that is color Banding. If your source footage has it, then
not much you can do to completely remove it, even if you render
it in 32bit.
There is however some plugins that has a Debanding filter that
can help a little bit, one such plugin i know of is Tiffen DFX 4 OFX
for Sony Vegas.
Steve Rhoden (Cow Leader)
Film Maker & VFX Artist.
Owner of Filmex Creative Media.
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