How to treat XAVC S file in Vegas?

Former user wrote on 1/6/2023, 5:17 PM

No, I save as full range.

Best of success, and welcome to the forum.

I tried using your LUT but it goes out of scale.
https://i.imgur.com/1E2Uddi.png

The upper range is OK.
https://i.imgur.com/NR0ko0G.png

What is the advantage of using a LUT instead of a Brightness&Contrast filter?

@rgr I"ll tell you the disadvantage of a LUT, it's destructive, you can rarely reverse the actions of a LUT in color grading. It is why in another thread about grading HLG, RogerS and (sorry I forget his name) were using color space transformations, not luts. to try and make HDR look right, Vegas can see all the data on your original file with a color space transformation, and at the right bit depth that information is also transferred to your encoded file, but with a lut, that data is lost.

I'd be happy to be corrected about this

RogerS wrote on 1/7/2023, 1:07 AM

For the other thread on a phone with Rec 2020 HLG, I would use a custom-built LUT if one were available for that phone with those settings. The results for HDR on phones with 32-bit ACES transforms just weren't visually appealing to me and require more work in post.
In general I think of color correcting like bobsledding- the fewer moves you have to make the better and if you can get to the end point with a single LUT vs a transform and a couple of color correction Fx even better. If low internal precision is an issue you can always apply the LUT in 32-bit mode.

Is there an inherent advantage to a LUT over brightness and contrast? I don't think so. I wouldn't use that Fx for this purpose though, I'd use levels.

If you're in a full range project make sure scopes is not set to studio/video range though.

Former user wrote on 1/7/2023, 7:48 AM

Is there an inherent advantage to a LUT over brightness and contrast? I don't think so. I wouldn't use that Fx for this purpose though, I'd use levels.

I haven't been keeping up with color correction on Vegas I know it's evolved a lot. That doesn't work for Premiere and Resolve (I think most NLE's) as contrast values are S curve, but if Vegas's default is still linear contrast then contrast plus offset should work (plus a good eye) without anything else although it's almost artistic interpretation as to the result, which isn't ideal for color correction rather than a stylistic grade. The other gentleman was able to do quite a good job.

Aces transform is destructive and so are luts. Yes I think I agree, a lut on the final color correction node, and forget about ACES

RogerS wrote on 1/7/2023, 8:31 AM

I assume brightness and contrast is this Fx which is ancient, right?

I don't see how you do anything precise here.

For computer/video range conversions for 16-255 I think you should just do a precise conversion (LUT or half of the stock levels correction). While the color grading panel could do it you're kind of wasting it as you only get one per chain and it's slower than other Fx anyway.

Resolve's color space transforms are nice as you can mix and match gamuts and gammas. With ACES you're stuck with whatever combinations it comes with and if it doesn't look right it's hard to fight with.

I just compared Slog 2/sgamut with one of my cameras with ACES and also Leeming LUT and while I can get ACES to the right place with a bit more work in the color grading panel the LUT is just a better starting point. Maybe with a different camera or setting ACES would be the better choice.

Howard-Vigorita wrote on 1/7/2023, 11:05 AM

I assume brightness and contrast is this Fx which is ancient, right?

I don't see how you do anything precise here.

It's got the same decimal precision as the color wheels in Grading and potentially greater resolution than you'd get with medium resolution 33-point LUTs that Vegas makes from FX chains and Grading. And definitely more precise if you animate it with key-frames.

RogerS wrote on 1/7/2023, 11:21 AM

How would you precisely use this to change the luminance of a clip from 255 to 235? (or define it as full range and reduce black from 16 to 0)?

rgr wrote on 1/7/2023, 3:44 PM

I assume brightness and contrast is this Fx which is ancient, right?

I don't see how you do anything precise here.

Of course, you can use other combinations of values to get the same effect.

(Project, videoscope, file color range -- all set to full range, 32bit)

Howard-Vigorita wrote on 1/7/2023, 5:12 PM

How would you precisely use this to change the luminance of a clip from 255 to 235? (or define it as full range and reduce black from 16 to 0)?

@RogerS That's what the Levels FX is for. I only use it with limited-range projects to achieve a standardized viewing reference for editing. What I prefer, however, is SeMW which is a true view-transform and functionally identical to Levels FX; the only difference being that as a view-transform it does not need to be turned off for rendering. If the project is set to full-range, no need to be remapping levels back and forth or converting the clips. Just edit as usual by eye, looking at the waveform scope and the preview, regardless of whether using Color Grading wheels or any other FX. If I want more control over level redistribution, I use the contrast center adjustment in Brightness/Contrast FX, gama in Color Wheels, or midtones in RL Color Wheels.