Banding

[sam karr]

When I underexpose my footage in redcine-x I can see banding appearing at a certain point. Is it something normal?

[Armen Shandi]

Sam,
What exactly do you mean by banding? Can you post a screenshot or send it to redcinex at red dot com? thanks.

Armen

[Joseph Coleman]

its from your monitor believe me. if you zoom in you will see the banding patterns change.

[Matt Ryan]

Your monitor is most likely 8 bit and if it's more high end maybe 10 bit. Your footage from a Red One MX is 12 bit and Epic/Scarlet is 16bit. Your monitor cant display the complexity of the higher bit rate so it causes banding. It's not how the footage actually looks rather how your monitor displays the image.

[sam karr]

here is the normal exposed one: http://www.supralumen.com/original
here is an underexposed in redcine-x one: http://www.supralumen.com/banding
It's a imac 27" screen for info.
So maybe you will not see it on your screen.
I just don't understand why the image is perfect when exposed quite normally, even on smooth gradients, but has a lot of banding when exagerating the iso toward under exposition.

[Matt Ryan]

your adding in more contrast and more gradations of grey/black. It will cause more banding. Im using a 30" Apple Cinema Display that has been calibrated. I see banding on almost all of my contrasty and dark footage. If you zoom into the footage 100% and scan the areas you won't see it.

[sam karr]

Ok thanx for your replies.
I'm seeing it even at 100% in fact.

[Matt Ryan]

Ok thanx for your replies.
I'm seeing it even at 100% in fact.

Is your monitor calibrated?

Both images look identical to me (banding wise). Im judging by the wall on the right.

[Marc Wielage]

Be aware that all the Apple displays of which I'm aware are 8-bit.

Take your footage to a decent post house with 10-bit broadcast monitors and ask to check the footage there. A lot will depend on the nature of the exposure, the compression rate chosen, and the degree of change introduced during the color-correction process.

[David Rasberry]

I see no banding on the correctly exposed image and significant banding on the under exposed one. 16 bit AD or not, when you under expose you throw away most of the available bit depth at the top end of the scale and there are fewer bits left to define values at the low end. Why are so many people continually under exposing footage when it isn't necessary? If you are not clipping highlights, the more exposure the better. Whatever happened to the ETTR principle? ( expose to the right end of the histogram for a "fat" image).
If you under expose film you get bad results, if you under expose digital you get bad results.