Problem in banding preview

[Jo artmm]

Hi everyone 

I'm editing my foteage on premier pro, i filmed 10-bit but when I'm editing my foteage I see banding, I did my research but nothing works I start doubting on the my foteage, I tried it in other place and the banding is in my foteage, I contacted the camera factory, they answered me and they said that I have to to adjust premier sittings to max depth in preview.

How I can do that in premier, how I can change max bit depth in preview and render ?

I attached a picture with the problem I have

 

Thanks in advance 

[Sumeet Kumar Choubey]

Hi Jo artmm,

Please navigate to Sequence > Sequence Settings to enable Maximum Bit Depth for Video Previews. Also, are you seeing the banding after doing any heavy color grade or just by importing the original media in the timeline?

Thanks,

Sumeet

[Jo artmm]

Thanks for your answer, here in attachement i attached my sequence sittings if you can have a look at it.

No i don't see any banding till i start correcting and speacialy when i put the Black down and white up, because im correcting LOG foteage.

[R Neil Haugen]

What's the camera? And how are you normalizing the log encoding to Rec.709?

I see you're working anamorphic too ...

Neil

[Jo artmm]

Im filming with ZCAM E2S6, Yes Anamorphic 

I just normalize it with Lumetri color by adjusting the Basics but i feel that there is a better way to do it.

I tried the Zlog plugin from Zcam to normalize but it dosen't really work good for everything, some yes and some no.

So if there is anyway to save this images it will be great help.

Thanks in advance

[R Neil Haugen · Accepted solution]

First, if using a manufacturer's LUT for normalization, apply it via the Creative tab LUT slot, NOT the Basic tab!

Second, do NOT use the Blacks tool in the Basic tab to drop your Shadows darker. It will cause banding if you do. It's only useful for a few points of change of the actual black point.

Why for both? I'll start with LUTs.

Colorists call LUTs the "dumbest math out there" for a reason. There's no subtlety to them, they're a simple math table matrix operation. X pixel becomes Y. And built on an ideal exporuse in an ideal lighting setup for contrast and saturation.

Field produced media rarely matches the exact lighting/camera setting combination of the LUT creation process. So ... you need to be able to apply the LUT, then trim the clip's exposure ... the white point, black point, contrast, and saturation ... "into" the LUT while viewing the image and the scopes.

In Resolve, you apply a LUT to a node, it's processed after any changes you make via the color controls in that node. This is correct. Premiere's Basic tab ... isn't. They're even thinking about changing that processing order, putting the LUT after the controls.

So apply the LUT in the Creative tab, trim all the tonal controls in the Basic tab, it will work better.

For manual normalization, here's my suggestions. Including why the Blacks tool is so limited.

First ... the Contrast control is the best for much of the needed expansion, BUT ... it always is based on expanding outward from the 50 nits middle of the RGB Parade/Waveform scopes. So use the Exposure slider to move the signal in the Waveform scope so the the middle of it is centered on the 50 nit  left side marker, then use Contrast to expand evenly below and above that 50 nit marker.

For fine tuing the white point, the White tool is more specific than the Exposure tool. The Whites tool is like grabbing the right end point of the RGB Curves tool and moving it around. The Exposure tool lifts everything, but ... it's like grabbing the middle of the RGB curves and lifting. Stretching out the Shadows, compressing the highlights up to the white point.

For shadow and highlights area fine tuning, work the Shadow and Highlight controls.

Do NOT use the Blacks tool for anything other than a 2-5 point shift in black levels! Just ... DON'T!!!

The Blacks tool is rather odd, it's like a swinging gate/door at around 12IRE/nits. It will not affect the clips above that, so it simply creates banding if you use it to move  shadow data down.

So use the Shadow tool to set your general low values, and only use the Black point for a very minor change.

Neil

[Jo artmm]

Well i can't thank you enaugh for taking from your own time to explain to me all of that, in this moment that i need help.

I tried everything you adviced me with and i tested it, and it's actualy did a quite better job, if you can have a look on the screenshots that i attached and tell me you think about it. (The one with red line i did Mask and put down the White to cover the banding even more)

And i want it to ask your opinion about Zlog plugin, because it's even giving me more banding, and the sitting are so complicatd to adjust. 

Thank you so much again and again.

[Jo artmm]

Sorry i attached Screenshoots when Proxy was activated. 

This is original 

[R Neil Haugen]

That is a very high-contrast image, and with that large area of smooth wall and very slight gradations across it, well ... it's a natural issue for banding to appear.

What lighting besides the lamp in the image is used for this clip?

Neil

[Jo artmm]

(very high-contrast image)  It is a good thing or a bad thing .. lol?

Im filling the room with Blue LED lights, and im putting very bright bulb inside this lamp.

So for your opinion banding is normal to appear in this sitatution?

[R Neil Haugen]

Heh heh ... a room with dark blue LEDs and one very bright practical ... with a smooth wall to boot light by the blue LEDs ... let's say, I'm not at all shocked?

Banding comes about when the levels of something are pushed past smooth boundaries. It's easy to visualize it when say you have 260 levels of values over a 255 level screen. It's pretty easy to imagine running out of data somewhere, and getting a couple 'blanks' where there isn't a smooth gradation anymore, it jumps.

But even if you've got quite a few levels to deal with, if you push past certain amounts, especially across smooth surfaces of the image, you'll get banding.

That dark deep area doesn't have much pixel data in it. And it's chroma data is all pushed to pretty much one hue. And then you push the luma data too ... bongo, it breaks.

You might do better with a bit more light into the shadow areas, so there's more image data there to begin with. Then when you push it down in post, you've got data to push around.

Neil