> Darren New<dne### [at] sanrrcom>  wrote:
>> OpenEXR stores more than 8 bits for each pixel. Dithering (WIYF, btw) moves
>> pixels small distances in pseudo-random directions in order to blur the
>> edges of the bands, essentially.  http://en.wikipedia.org/wiki/Dither
>
> clipka<ano### [at] anonymousorg>  wrote:
>> Yes. But note that a lot of image processing software can't read OpenEXR
>> yet, so I'd have to redirect you to IC there, too - so at least for
>> starters you may get just as far with 16-bit PNG and IC.
>>
>
> Thanks for explaining this on my humble level.
>
> I've converted from 16 to 8-bit PNG with IC, but have seen little change
> (still banding). I'll try 3.7 and OpenEXR next. Otherwise changing the sky in an
> outside application might be an option that just came to mind. Maybe I can
> achieve a little less banding with that. So you might hear from me again, or not
> :-)
>
> Very gratefull for all the quick replies.
>
> Joost
>
>

Even if you render at 16 bits per channel, your display is still limited 
to 8 bits per channel. Thus, the pixels get down sampled for the 
display, resulting in the banding you see.
You can hide some of the banding using some noise on the red and green 
channels.
It can be a mostly transparent pattern layered over the blue gradient 
using a noisy pattern like granite or bozo scaled small enough.



Alain

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