FS5 S-log tips and gotchas

[Nigel Davey]

I just found this video which details all the Cinegammas and S-log profiles:

YouTube (Short URL)

It's a shame this wasn't out when the FS5 was first launched. It would have helped a lot of folks given how little info was released re factory preset FS5 profiles. But on the whole this video fills in the gaps.

That said it is frustrating Alister recommends shooting 1-1.5 stops above the FS5's S-log exposure baseline. I assume he's correct. But if so it makes Sony's baseline irrelevant. Worse still, a complete hindrance since the Gamma Display Assist is inevitably wrong and must be made to look overexposed to get a desirable slog exposure. Which begs the question, what is the point of it?

Is this a case of Sony needing to come clean and admit their slog exposure basline is wrong and subsequently adjust the Gamma assist in a firmware update.

[Cliff Totten]

That is why I said up in an earlier post that I dont use the built-in Sony assist function. I load Alister's SLOG-2/3 +1, +2 and +3 LUTs in my Shogun and Pix E5.

Try this as a very simple and quick test. Toss in SLOG-2, go outside and shoot one scene in full auto using +/- 0 EV. Let the FS5 pick what it thinks the exposure should be. Then do the same shot again but run the auto at +1.0 stop brighter. Do the shot again with a +1.5 EV auto over exposure. (for this auto test, don't worry about how bad your monitor looks or where your zebras are for this as only the camera is doing the judging)

What happens when you load those files up on your NLE? Without knowing anything about the scene type, I'm guessing that when you add contrast back, you are forced to lift the 0EV in post. If you lift it 3 or 6db , the noise can come right up with it. What about the +1 and +1.5? I'm guessing there is a better chance that the contrast center is closer to where it needs to be and will not require much, if any lifting. If anything, you have a good chance of being able to bring it DOWN -3db or more. The more the better because doing this hides the noise floor and helps your image look cleaner.

Alister's +1-2 stop over rule works VERY well. You can trust it!. You can sort of think of it this way,...Slog "compresses" brightness. This allows you to "pack" more brightens into the recording and pull the levels down to where they "really" belong in post. (expanding contrast in a more downward direction)

This all sounds complicated at first but just try the 0EV and the +1EV and +1.5EV scenes and watch the affects you see in you NLE. See your scopes? (Try a -1EV too!...just for the fun of seeing how bad the normalized video might look after you try to lift THAT in post)

CT

[Doug Jensen]

Originally Posted by Nigel Davey

That said it is frustrating Alister recommends shooting 1-1.5 stops above the FS5's S-log exposure baseline. I assume he's correct.

Alister's over-exposure rule?! Surely, you've got to be kidding. He's finally just saying the same thing many of us have been saying for years -- that you don't really need 49 IRE of headroom above 60% just for highlights.

Everyone I know (who's work and opinion I respect) that shoots RAW or S-LOG with ANY of Sony's cameras (FS5, FS7, F55, F5) ignores Sony recommendation of 60% white. I don't know anyone who follows Sony's advice. In fact, in my FS5 master class video, that I produced many months ago, I specifically recommend 75% zebras on white for S-LOG (see chapter 12), which produces video that is 1.5 - 2.0 stops overexposed compared to Sony's guidelines. So Alister and I are saying the exact same thing. aAd when we agree on something, you know we must be right. In fact, that is the advice I've been teaching for at least THREE years. Exposing a couple of stops aboe 60% is standard operating procedure for everyone in the know. This not anything that came from Alister -- and if anything, he was late to come onboard with the rest of us.

Also, even at 75% you aren't going to "pull down the levels" in post. They are still going to be too low. You're always going to be bringing UP the levels from 75% to 90% -- or higher -- to get a finished image.

Furthermore, anyone who knows anything about grading S-LOG or RAW in Resolve also knows that you don't need special LUTs to compensate for exposure variations. That is all just nonsense. You simply adjust for exposure on the the first node and then apply a LUT (if you choose to use a LUT) on the second or third node. It's very simple.

If you want to shoot S-LOG, all you you to know is:

1) Choose S-LOG2 for uncontrolled light situations ( outdoors, run & gun, documentaries, wildlife, etc).
2) Choose S-LOG3 for controlled lighting situations (sit-down interviews, faces, drama, indoors, etc. )
3) Expose bright reflected whites at 75% by using zebra 2.
4) Always grade in Resolve (BTW Resolve is free so there is no reason not to have it)

That's all there is to it.

[Cliff Totten]

I dont know about anything you and Alister might or might not have between each other. I can only tell you that he has been saying this for a while. This video is not the first time. I do know your excellent videos but I'm more familiar with Alister and I have been reading his site for a very long time. Alister has also been a Sony spokesman for a long time now.

I do think that Sony should give a couple of gamma assist options inside the camcorder. Like a +1 or +2 option.

For me? I protect my highlights like everybody else but I do often expose as much and I can safely get away with to see further into the shadows. (depends on the scene and how much I'm looking for) So, I'll press SLOG fairly hard to get as much as I can out of it and I have learned to get the results I'm very happy with.

My biggest advice to Nigel is try it at different levels and see how that affects his grade.(good and bad) Like you, Alister and others have said, you need to push it a stop or two, possibly more. For what I have seen? That's a huge difference in the grading experience. Noise can be nasty in SLOG so you do whatever you can to mask it on post.

The best way to learn SLOG (one of them) is to see what it looks like when it's screwed up in post.

Here are two SLOG-2 frames, before and after. Just two shots in my backyard on a VERY sunny day in Florida. There are shadows in both. Some cats in the tiki hut and very dark shadows in those elephant ear leaves. I shot this very hot with whites near 100 on the scopes with little "specs" reaching around 105-ish

Both theses wave forms were contrast stretched downward and brights lowered. (Nope these aren't perfectly broadcast legal, white balance is cold and this is a quickie. Never meant for anybody to see these!) This was a test a while back to see how far I could push the FS5 in both directions.

See here ----> https://drive.google.com/folderview?...zg&usp=sharing

CT

[Patrick Baldwin]

Just wanted to say thank you for this thread! As a new FS5 user and inexperienced in general this is incredibly valuable to me.

[Cliff Totten]

Dont use SLOG on a paying job or serious job right now but also don't be afraid to experiment with it either. Honestly, SLOG is great, but there isn't a strong need for it in many common situations. I find it really only good for outdoor extreme dynamic range scenes. For indoor work I just can't imagine myself using it. And certainly if I have controll of lighting, I don't think it's necessary.

SLOG puts a strain on an 8 bit, highly compressed CODEC and why beat up that CODEC if you aren't going to reap that much benifit in the end?

Every scene is different and only you can really determine what the subjects exposure needs to be. Skin tones? A dark colored animal in front of a bright waterfall? A pure white orchid in a shady garden? A women looking out a sun lit window? Whatever it is, It's your call. It's your art. SLOG is just one tool to use. Experiment with it first with shooting and try many grades and coloring before you begin to rely on it for jobs.

CT

[Doug Jensen]

I'm not disagreeing with the advice to do your own testing until you become comfortable with S-LOG or any other mode the camera offers, but I will say that shooting S-LOG shouldn't be scary. In fact, it's actually easier and more foolproof than Custom because it is so forgiving if you don't nail the exposure or white balance as closely as you'd ideally like. "Fix it in post" used to be a joke, but with S-LOG and the great 10-bit codecs we have at our disposal today a lot of stuff can be fixed . . . or improved in post. But with the Custom mode, things are a lot more baked in and harder to change after the fact. Of course the caveat is that you need to have some grading skills and decent monitors to get the job done right. You can't just blindly throw a LUT on all your S-LOG footage and walk away -- that's not grading.

[Nigel Davey]

Well I've put together 30 secs of clips from my first venture into S-log. It isn't perfect, but I've learnt a few things during the shooting and editing process.

Slog experiment 25p on Vimeo

When I have time I'll go back and edit some of the 709 clips from the same shoot to see just how far I can push them in Post.

[Doug Jensen]

Real nice. I think you have nailed S-LOG already.

[Cliff Totten]

Very nice. It's a very "warm" look with mild tones. The sky gradient is interesting too. Nice job. Nice movements. Where you on a jib and /or gimbal?

CT

[Nigel Davey]

Thank you both. But in reality I found it very difficult to get to this stage. Since I am (as yet) unfamiliar with Resolve I had to use Premiere. 90% of my footage had the flashing discussed in the other forum. With what was left I constantly had to battle a green tint, despite setting all three FS5 slog profiles to 5500K. Not sure why it was there.

In Premiere I started with Lumetri corrections but often had to resort to other correction tools. So on the whole it was not fun.

Doug I realise Resolve is probably the answer. I just need to carve out time to learn it.

Cliff, yes I used a small Kessler jib for verticals and a mini dolly for horizontals. I've considered a gimbal system like the Ronin, but may wait and see if an Osmo Mkii (I assume there will be one) is a little more user friendly. The sky is a straightforward gradient from my Red Giant Looks plugin.

Again thanks for the encouragement.

[Cliff Totten]

Color shifts are something I see allot with SLOG 2 but not very much with SLOG 3. It's my guess it's because SLOG3 is more linear than SLOG2?

I tend to play with curves for each RGB channel. I might say "Let me pull the mid-tone blue's in" or maybe later "brighten the low end green" A slight change to one channel will affect the other two.

Sometimes I increase the saturation so it's too strong first. This let's my eyes see where things are blatantly wrong or off. I then fix it in the heavily saturated look first, then after I think it's balanced, I pull back the saturation to where I think it's natural.

The grading tricks are endless. Everybody has their own way of getting there and there is no real "wrong" color grade.

OK,...yes, I think the only "wrong" thing you can do is to add a plugin that pulls a level down and have another that pulls it right back up behind it. If you stack plugins that stretch chroma/luma in "opposite" directions at the same time, they can pull an 8 bit codec further apart and cause too much separation. (competing plugins hurts banding)

Have you seen "Mad Max: Fury Road"? The yellows are VERY deep and explosions are extremely dark red/roange. The movie is extremely bold in its color grade. Then look at "The Revenant" That move is extra blue and cold whites and the saturation is reduced to create a desolate, dark "feel". It's the exact extreme opposite of "Mad Max: Fury Road". Both are extreme and both are great.

Resolve is awesome. But you can color grade with many products. I think it's more about training your eyes to spot what is wrong and learning to shift things in the real direction you want them move. Sometimes I say "Yuck,..I dont like this tint/color so I'll tend to "push away" (very lightly) form that color into the direction it's opposite color. So if I say" Ehhh...too green"...I start pushing CAREFULLY over to the red or violet or orange direction. If you dont like a tint head to it's opposite color to balance it. Every NLE has a brights wheel, a mid tone color wheel and a shadows color wheel. They are your friends.

I think that grading Slog takes more practice than learning to expose it in the field. That's why I say the SLOG work flow requires two different skills.

CT

[Alfred Okocha]

Originally Posted by Doug Jensen

If you want to shoot S-LOG, all you you to know is:

1) Choose S-LOG2 for uncontrolled light situations ( outdoors, run & gun, documentaries, wildlife, etc).
2) Choose S-LOG3 for controlled lighting situations (sit-down interviews, faces, drama, indoors, etc. )
3) Expose bright reflected whites at 75% by using zebra 2.
4) Always grade in Resolve (BTW Resolve is free so there is no reason not to have it)

That's all there is to it.

Hi there!
I just got a job for next week where I'll shoot s-log for the first time. (S-log 3 to be specific.) I won't grade it, they'll have experienced people for that. I just want to know I get the exposure right.

I just went out and shot some seconds using Dougs third rule up there. I applied the pre made SONY s-log 3 in FCPX and the exposure looks quite right. (I brought down the highlights a little notch since they were a bit over 100%)
1. Is it really that simple? (Considering all the warnings everywhere about shooting it.)
2. What should the zebra 1 be set at for skin tones?
3. They want some shots at late evening. Any tips?

Thank you very much!

[Alfred Okocha]

Here's a screen shot by the way.

[Doug Jensen]

Originally Posted by Alfred Okocha

2. What should the zebra 1 be set at for skin tones?

None. You don't expose for skin tones because everyone's face is different.