Photoshop tip #32 - Good gradations:
Ever been working in photoshop and had the dreaded banding issue show up while doing gradations - especially visible when using multiply layers? Well, your bandwidth (BITS) per color may be on the low side and that's what breaking up your gradations. So how do you solve this strange banding gradation problem?
Answer (and it took me a long time to figure this on out):
Bump up your Bits per channel in PHOTOSHOP from 8bit per channel (default) to 16 bits per channel: Image=>mode=> 16Bits/Channel.
Here is a GREAT article on this very topic:
The down side of 16 bits per channel?
1) Massive file sizes. Simply put, the memory/file size of your image size will double.
2) Slow big or tricked out (complex) brushes. In the case of photoshop's new brushes - read that as REALLY SLOW big brushes.
A lot of my layered production work gets well into the 700meg+ range and the thought of saving multiple 1.4+ gig PSD files is simply impractical for a lot of the Production Design work I do. BUT, 16 bit is much nicer when doing high end illustrations (with decent multiply-gradations) so...
My current rule of thumb: If it's not banding, stay 8bit. If you need higher fidelity and can afford the huge storage/memory/speed hit - go for 16 bit as the extended range is a beautiful thing.