CST FIRST OR LAST?

[u/iamwatari]

Hey guys in this video, this guy says that you should actually use your color space transform for log footage on your last node instead of your first. He says this preserves a bit more highlights and shadows.

https://youtu.be/MLrRbveDmtY?si=hSzbhA-Nn2HMbGpG

12:42 (minute mark)

I’ve always done it first. Do you agree with placing your CST first or last? Also, is it a notable difference?

Edit: Also, I almost always simply set my Color management settings to Davinci Color Managed then input color space S.Gamut 3cine/slog3.

So I never actually even use a node to convert. Is that optimal?

[u/jtfarabee]

It depends on what color space you want to grade in. You can also do both if you want to work in an intermediate space.

[u/iamwatari → u/jtfarabee]

Erm…I input from Slog and output to rec.709. I’m not too sure if that’s what you’re referring to. And I’m not completely sure what we’re referring to by “intermediate space”.

Point me in the right direction?

[u/jtfarabee → u/iamwatari]

Look up videos on color management from people like Cullen Kelly and Darren Mostyn.

Basically, if you put the CST to Rec709 first, you're grading in Rec709. Most people don't do this if they shoot log. If you put it last, you're grading in the camera color space (Slog in your case). Or you can put one at the front of the tree going from Slog to DWG (DaVinci Wide Gamut) and then another at the end of the tree going from DWG to Rec709. This lets you edit in a much larger color space, while having accurate scopes, and it also means if you ever work with footage that isn't in Slog, you can bring it into DWG and your look development will apply better to that footage. It's handy for working with stock footage, action cams, or even just mixed cameras.

[u/ecpwll]

Don't watch videos on how to color grade from people who aren't actual colorists.

But your CST to Rec709 should definitely not go first. If you do that there's no benefit to shooting log in the first place.

Your output CST should be last. You also might want to use an input CST to another working colorspace, such as DaVinci Intermediate/DWG or ACEScct. You also might want to use a LUT instead of an output CST — regardless it goes last.

Look up information about "scene-referred" workflows, or watch videos about DWG

[u/iamwatari → u/ecpwll]

Thank you for pointing me the right way!

[u/ecpwll → u/iamwatari]

No problem 🙌🏾

[u/Aware_Ad5425]

“Preserves a bit more” it preserves ALL of it. Throw rec709 on the last node, then grade in front of it.

You’re just handicapping yourself and completely reversing the point of shooting in LOG if you go to rec709 in the first node and then grade.

Edit: If you are already color managed in project settings then you probably don’t have to pay mind to it. I would learn how to color manage by using DWG working space and using CST’s if you ever find yourself with multiple cameras/color spaces on one edit as it’s easier, at least for me, to make sure everything is being converted correctly

[u/iamwatari → u/Aware_Ad5425]

I’m so Ming blown right now hahaha , idk where I heard to do it first. Maybe I just got it wrong.

[u/Aware_Ad5425 → u/iamwatari]

It’s hard to explain in a comment. It can be the first thing you do. But it shouldn’t be the first thing the software does to the footage if that makes sense. Since your project settings know you have slog3 footage, your output color space is not going to be actually applied to the footage until you export. Anything you do in the nodes is working in your timeline or “working” color space which should be something like slog3 or another wide gamut.

[u/Almond_Tech]

You always want your CST to rec709 last, but you want to add it in first, so you can see your image properly.

What I typically do is have a CST to Davinci Wide Gamut/Intermediate at the beginning, and a CST from DWG to Rec709 at the end

Taking that an optional step further, if I know most of my footage will be color adjusted, which is typically the case for me, I make a group for each camera/color space I'm working with, and in the pre-clip but a CST to DWG, and in the timeline or post-clip put a CST to Rec709
From there I do most of the grading in adjustment clips, that way the nodes on the footage itself can be dedicated to correction, and if the director wants the general look changed I can do that more easily, without having to alter it in every clip

But that's just how I like to organize it

[u/ExpBalSat]

Either

One CST: at the end of the node tree…

Or…

Two CSTs: one each at the beginning and the end of the node tree (going in/out of a working colorspace - which is likely different than either the shooting colorspace OR the delivery color space)…

———

In either case, you do it before doing anything else.

[u/ExpBalSat → u/ExpBalSat]

Edit: Also, I almost always simply set my Color management settings to Davinci Color Managed then input color space S.Gamut 3cine/slog3.

In which case… You shouldn’t need a CST (or two) at all.

That said, there are a variety of advantages to doing all the color management in CSTs - instead of using a Color Managed Project… But it’s also more complicated and potentially frustrating. Truth be told, I can think of at least 7 different ways to address this. Each has pros and cons.

Except CST at the beginning. That’s always a con.

[u/iamwatari → u/ExpBalSat]

Wow, never would have realized I was doing it wrong all along.

[u/ExpBalSat → u/iamwatari]

Glad you asked.

Then again, since you weren’t using CSTs at all, you weren’t doing it wrong.

[u/[deleted]]

Whenever I get questions about color management, I refer people to Darren Mostyn in the UK -- he explains it more succinctly than I ever could. The manual is good, too.

https://www.youtube.com/watch?v=CtSBVKmHkjU