Lumetri Limitations

[Offbeat Bryce Productions]

I'm very confused after watching this video.

I don't have any of the problems described in this video. Anyone else having the same issues as this person in the video?

Perhaps maybe it's the codec he's using?

He's saying the scopes don't accurately represent  what he does in Lumetri even though my AVCHD does.

[Peru Bob]

Please don't double post.

I've deleted your other thread with the same question.

[chrisw44157881]

I'm impressed someone made a video like that. How did you find it? I use fast color corrector myself. you can get around part of the bug by laying a rgb effect and raising/dropping all ire values in the waveform to 0-100 ire or else lumetri goes crazy.

if none of your footage is below or above 0-100 ire, you probably won't have this problem. as to RAW controls being better, well heheh, yea, they are. also, any extreme shadow problems require enabling hdr in lumetri. Think of lumetri as beta. heck there's still no color management after 10 years.

[Jim_Simon]

The cameras I use record the full range, not limited.  So if there are "overbrights", that detail is either gone for good, or brought back into range with the RAW settings.  So for me, this is not an issue.

[Ann Bens]

I know of this video and the editor who made it.

I have encountered this many times.

When i do I resort to the 'obselete' effects.

[R Neil Haugen]

Jarle is a very, very good post-processing expert. He's knowledgeable, experienced, and also a pretty nice guy.

And I can guarantee what he says is accurate with any media that comes into PrPro with over-brights and super-blacks. Lumetri behaves exactly as he shows. And no, he isn't saying the scopes inaccurately show what he does, but that they show exactly where his media is, and what Lumetri does with it. And everything he shows that he feels is "broken" will happen exactly like that with any media that includes signal data in the "overbrights" above 99, or the "super-darks" below 1.

And that is how it is designed to work.

Yes ... I've spent plenty of time in both live discussions and emails with some of the PrPro staff, and that is exactly how it's designed.

The basic concept behind Lumetri was to create a color workspace that could sort of replace the full grading app SpeedGrade for many users. And if you have any familiarity with the Adobe Lightroom still-image program, you'll recognize the basic layout of panels of tools, on the right side of the UI, exactly like ... Lightroom. And the Basic tab is the closest section of the Lumetri panel to Lightroom. This is by design ... that's not a layout used by any pro colorist application I'm aware of.

Next, the processing of the media occurs precisely in the same order the tools appear on the UI, top to bottom. So ... in the Basic tab, any Input LUT is applied; then Temperature, then Tint, then Exposure, then ... on down the panel. And on down through the other panels. (Which does lead into his comments about the HSL Secondaries also.)

But also inherent in the design considerations was that they were building a tool mimicking a non-pro-video program, that to their expectation would be most utilized by those without experience in pro video media. "Noobs". And this is the exact phrase that's been used by several of the engineers/design leaders to me in explaining this design choice: "This was designed to keep the users from breaking their media."

The Basic tab tools are limited to working with media within 1-99 on the Lumetri scope's RGB Parade left-side scale. Completely. You can not push media above 100, neither can you 'touch' super-darks at or below 0 on that scale. Unfortunately this means that if you currently have data above 99/below1, it's off-limits for any slider of the Basic tab to modify.

Those bits where his clouds are above 99, and when he brings down the Whites, you see the scopes now show a major gap between signal at whatever the top is ... maybe 85 ... and then no data at all until it hits 100, then there's all that data up there? Yea, that's absolutely correct.

My Panasonic GH3 creates mov, mp4, and AVCHD files. All of those formats can easily provide media that exceeds the 0-100 scale on the left side of the RGB Parade scopes. In direct terminology, "over-brights". And exactly as Jarle shows, no over-brights can be "touched" by the tools of the Basic tab.

There are two tabs of the Lumetri panel that are allowed to touch signal in over-brights/super-darks: Curves and Color Wheels. So, you can just skip down to the Curves tab, bring the top of the signal down, then go back to the Basic tab and work, right?

NO.

The controls of the Basic tab are applied to the media first, remember? Anything you do in the Basic tab changes the signal that any later tab "sees" and can modify. So now, any adjustment of say the Whites or Contrast sliders in the Basic tab throws the over-brights back up, creates that huge gap, and gives you an incredibly banded image. So if you go down to the lower panels to correct your too-bright media, you can't ever go above those and touch anything. Period.

That's why the HSL panel also gets screwed up if you go back & change the data in an earlier panel. The HSL mask and contols should work on the basic media signal data, but they don't. They are processed in order, after everything you've done above. Which is logical to the engineering staff, and terribly screwy in working media. So ... you have to learn to work in the order of the tools they give you.

You wanna know some other screwy design choices?

The Basic tab's Input LUT is where one is supposed to use a camera or technical corrective LUT. So if you're shooting a big Sony with a particular LOG format, you'd put the corrective LUT to Rec.709 there.

Which is completely ... WRONG.

All the camera makers build those LUTs around the sensor's design and the math of the internal processing ... from media that's perfectly exposed & white-balanced. They couldn't really do it any other way. So to properly use those corrective "tech" LUTs, you need to feed them a properly exposed/white-balanced image. So ... you need a spot to apply the LUT, then before that LUT, do the correct neutralization work while watching the results in the scopes & playback monitor. Completely backwards of this design.

(Note: all the camera manufacturers, colorists, and other software programs such as Resolve apply LUTs after neutralization. Only PrPro does it in this order.)

So ... what the heck do you use that Input LUT slot for? If you have media you're working like my little GH3 puts out that typically has over-brights, you load your media on a timeline, without any other corrections, then use perhaps the Curves or Color Wheels controls to bring the media tops back down to probably about 97-98, then save that as a .cube LUT from the Lumetri fly-out menu. Save it in the Technical folder, and give it a name that is like "1 Overbright Recovery" so it's at the top of the drop-down list, and you can access it fast to get your media workable in Lumetri.

There's a bunch of others, but I'm already into the weeds.

That said, Lumetri when worked with an external control like a properly (and nearly completely!) re-mapped Tangent Ripple or Elements panel, can do pretty good work and that pretty fast.

Neil

[chrisw44157881]

nice post neil! without your insight into the broken superbright problem, premiere would be mostly useless for a great many people. I almost left to davinci from this, for real.

Your post, """1 Overbright Recovery" Lut""

Are you talking about using master clips? Because that seems like it would be used the most. or.. wouldn't you need 2 copies of lumetri then, for technical lut?

What do you think of using an adjustment layer above video, set transfer mode to luminosity and apply levels effect and save as preset.

I made a preset for broadcast legal, which in hindsight, actually is almost the same thing! perhaps just need to raise output instead of input> 235 and lower <16  in terms of ire for non-broadcast stuff so it reduces instead of clips.

I did try going the route with a technical transform lut but premiere seems to have a bug where you have to nest your sequence first for it to clip luma/colors correctly without smooshing gamma. That's annoying as heck. I must investigate further.

[R Neil Haugen]

As to the overbright LUT, no ... you can make some settings in Lumetri, then go to the three little bars to the right of the "Lumetri Color" name at the top of the panel, right-click, and choose "Export .cube ... ". Then save that to the Program files/Adobe/Premiere Pro 2017/Lumetri/LUTs/Technical folder.

After re-starting PrPro, when you click the drop-down list for the Input LUT slot in the Basic tab, that LUT will be in the list. If you save it with the type of naming I suggest, it should be the first one shown. Which makes it very easy to apply that when needed. I have three different LUTs I created for various media there. Here's the shape of the curve for rolling off over-brights & super-darks that I did as shown in the Lumetri Curves tab, while watching the Waveform Luma & RGB Parade scopes:

(Having two "marks" close to each other is a way of forcing the curve shape above or below the paired marks on the line, otherwise it will bend the curve both above and below a mark.)

Using the curve shown above, I then created a cube LUT of this and saved it in the Technical folder ... so it appears at the top of the list. So that drop down now shows:

"1 Curve Rolloff" is the one that brings over-brights down and super-darks up a bit, as in the curve that is shown above.

"1 LowSat Mask" is a nifty one. That I created from a mask in the HSL panel, using Saturation only, where I set it for the low end of Saturation, the "full" bar up to about 25%, then the "shoulder" extending up to maybe 40%. Saving this just as a mask is possible ... on a "clear" clip with no other settings applied, you set the HSL panel like this:

And then do the Export cube routine as given above.

Now, when I set that 'on' in the Basic tab's Input LUT slot, the only parts of the image showing are the fairly low saturated areas. Which is rather nifty ... now set the Temp & Tint controls so that the low saturated areas shown by the scopes are centered in the Vectorscope, right on the axis of the two crossing lines ... and you've pretty well nailed "neutral" color balance. The low saturated areas in most images should be the areas closest to grey/white/black. Which normally belong as a spot in the center of the Vectorscope.

As soon as I've adjusted white balance, I select either "none" or the 1 Curves Rolloff if needed.

As to working on adjustment layers ... that's a good way to keep full use of the Lumetri panel, especially when working with external controls. If you have multiple Lumetri on a clip or AL, the color-workspace Lumetri panel will only work with the latest applied instance ... you need to use the Effects Control panel and the twirl-down controls to adjust earlier Lumetri controls. Which, naturally, will change how the following Lumetri instances affect your media also ... sort of a Harry Potter "wizard's" priori incatatem situation ...

So yes, I use AL's on sequences, primarily to A) maintain full use of my external controls (I've both a Tangent Ripple & Elements panel) or B) to extend a correction over multiple clips.

Neil

[chrisw44157881]

kudos, many users will find this extremely valuable and time saving. I never though of white balancing with a lut...lol! you should add this to your troubleshooting steps for "why doesn't lumetri work right."

[R Neil Haugen]

It's one of those things that occurred to me while sleeping ... or rather, in one of those moments like at 3am when you're actually almost awake and normally drop back off without ever realizing you were awake ... except my stupid brain suddenly comes up with this idea, which completely waked me up ... and immediately was contemplating whether it would work or not.

Took me an hour to get back to sleep!

But first thing next morning, had to try. First, I'd never heard of anyone suggesting you could export just the mask of an HSL key into a LUT, but doggone it, it worked! Second, how well would it actually work to white-balance "through"? Well, really ... pretty decently. And ... it's very fast. Apply LUT, adjust the Temp & Tint controls and you're basically there. The way I've got Temp (horizontal) and Tint (vertical)  middle ball axis mapped for the Ripple and Elements panels in the Basic tab, it's blazing fast.

And is especially useful on some of the harder-to-balance clips I've had recently. Finds the neutral areas, I center those ... and everything else seems to be within a "normally acceptable" range for the light it was shot under.

Neil

[Offbeat Bryce Productions]

So you are saying the curves in Lumetri fix the scope problem? I also just read something about using the YUV scope vs the luma

[R Neil Haugen]

First, remember ... this is ONLY an issue if your media has signal data up above 99 or below 1 in the Lumetri scopes. Most of my clips from my GH3 do, but some do not. For many others and with other cameras, this will almost never be an issue.

And ... it's not a scope problem ... not at all. It's a problem caused by the intentional design of the Basic and Creative tabs of the Lumetri panel. The development staff looks at the potential users of the Lumetri panel, designed to "appear" very Lightroom-ish, as probably not very experienced. So ... the controls they think most "noobs" will use the most, the Basic & Creative tabs, were built to prevent noobs from "breaking" their footage. With full intent. And as explained in person to me by several of the design team.

The controls for the Basic and Creative tabs are built with a limited dynamic range where they are allowed to affect the signal. You can't push data "out" of the 1-99 range, nor can you pull "outside" data into the 1-99 range.

So if your media has those ... "overbrights" and "superdarks" ... and you use the controls in the Basic tab to say try and bring the brights down, the controls will only affect the signal data below 100 ... from 99 on down. Any signal at 100+ just sits there.

Which results in a very clear and obvious "blocking" of colors and tones. And it does the same with any signal PrPro "sees" as below 1 ... leaves it there, so you can have total black and when lifting your shadows, nothing until you get up into light charcoal. A rather startling harsh line.

The Curves and Color Wheels are able to work with overbrights/superdarks just normally.

But they are processed after the controls of the Basic and Creative tabs ... so if you touch the overbrights/superdarks  and then go back up to try the Basic tab, you still don't touch the overbrights, as the Basic tab "sees" the signal before it's processed with effects from the other tabs.

So touching almost anything in the Basic tab after bringing overbrights down with the Curves/Color Wheels, makes it all go weird. Very ... weird. Inducing banding in tones and hues all over the spectrum.

So if your media has signal on the scopes outside of 1-99, you need to bring that back into 1-99 before applying any controls from the Basic tab to it.

Hence using say the RGB Curves effect applied before (above) the Lumetri effect in the Effects Control panel, or as I also showed above, create a roll-off Curves LUT, store it in the Tech LUT folder, and apply it in the Input LUT slot in the Basic tab.

Do either of those things, and you have full use of the Basic & Creative tab controls without your media going weird.

Neil

[tommyboy6567]

NEIL YOU ARE A FUCKIN GANGSTER

OP caught my interest because I too saw this video. I didnt really look into the facts of what he was saying but it definitely resonated with me. I use Lightroom heavily for my photography work and Lumetri seemed too good to be true. After many tests I concluded that It WAS too good to be true because i just couldnt get back what i needed in the lighlights. more tests and i began to think it had to do with the way I was exposing certain picture profiles or maybe the fact that i was only working with 8bits. I spent my time mastering exposure on the a7sii yet I still struggled to recover my overbrights. WHY!
I've always used 3 way color corrector or levels in the past but ever since upgrading my camera and PP, I've moved to Lumetri and never looked back. So much so that I NEVER EVEN CONSIDERED Lumetri would be designed in such a way. Clearly it is algorithmic but i guess I thought they would have got it right. I've worked through the quirks with the LUTs and the like but this just never crossed my mind.

I wanna crawl into a body bag thinking about all the shots I have ruined or just plain failed to fix based on my reliance on Lumetri,

I very rarely post in forums but I cannot thank you enough for taking the time to drop that knowledge. and the luts!?  INGENIUS

you the MVP.  You walked me away from the face of a cliff and handed me a blunt

[Ann Bens]

I thought the overbright issue was fixed.

[tommyboy6567]

sorry i was just voicing how much of a gangster neil is. issue solved.

[R Neil Haugen]

Thanks for your comments. Here's a blog post that demonstrates what each of the controls in the Basic tab actually do ... directly ... using a couple graphics elements I combined to show best which parts of the image move when working which controls up & down ... and some have very different patterns when moving 'up' compared to 'down'.

Lumetri Basic Tab: What do the tonal controls really do? – rNeilphotog

Neil

[R Neil Haugen]

The over-brights issue is sorta fixed for most media ... kind of. But for some clips from some settings in some cameras, you can still get bits that get left behind, or ... get stretched out quite a bit.

Not a lot of users should be having that trouble, but a few still will. Like ... me.

And the super-darks ain't properly fixed. Yet.

Neil

[Offbeat Bryce Productions]

Well I just tried adding fast color corrector and I can't make any different correction from the Lumetri panel

[R Neil Haugen]

I'm not sure I understand what you're talking about ... ?

Neil

[R Neil Haugen]

I'm still puzzled by this comment, so I think somehow we've missed each other's thoughts somewhere.

I wasn't saying the fast color corrector does something differently from the Lumetri. Bear in mind the math behind their controls is completely different, and that of the Lumetri is in general vastly better color science, though not a perfect tool for all purposes.

What I was talking about in this thread is limited to situations where the media has overbrights and/or superdarks, requiring a corrective tool to be applied to the media ​before​ the Lumetri effect "sees" that media.

So for the purposes of this thread, we're only talking about 1) media with overbrights/superdarks and 2) applying a different tool ABOVE Lumetri in the Effects Control panel, so Lumetri sees the signal ​after​ it's modified by the earlier effect.

I hope that's more clear now.

Neil

[Offbeat Bryce Productions]

ah,

Yes, I did misunderstand previously. I have a tendency to skip sections of what I'm reading due to my add. Still a struggle.

I think I understand what you are saying better.

How do I find out if I have footage above 99 or below 1? is that what the luma scope shows me? If so then I have a few clips here and there with the overall brights at 101 or sometimes 102 IRE but others are around 95 which I try to keep it to. My blacks are usually at 5 or just touching 0 but I've never had any clips below 0 if that's what you are referring to.

What do you recommend I have in the effects chain before Lumetri? Does it matter or is just anything such as fast color corrector or Curves plug in. I have a third party curves plug in I use sometimes as well.

[R Neil Haugen]

Yes, if the scopes are showing the signal up there, you got it.

The "obsolete" RGB Curves effect works well ... you can drag it onto the clip and then go to the Effects Control panel and drag it above Lumetri.  Go into the effect and pull the white down, or use one of the channels to pull down the offending channel.

Hence the Lumetri controls will all work as expected.

Something I'm using more now is a .cube LUT I created using the Curves tab of the Lumetri panel to roll off the highs a small amount and lift the lows just a couple points. I then exported that from Lumetri using the 3 horizontal bar menu at the top of the panel by its name.

I named it "1 softrolloff" and saved it in the Lumetri Technical LUT subfolder. It's the first thing when using the Basic Tab's Input LUT drop down list. And then the Basic tab works as hoped.

Neil

[Offbeat Bryce Productions]

A LUT is treated as another effect chain? Is that why you created a lut? I can't seem to find the menu to export a lut. Where is that?

[R Neil Haugen]

Yes, a LUT is just another Effect chain, in purest essence.

I've even created some for some hefty work in Lumetri, then "applied" a LUT Buddy effect on the clip, pulled up above Lumetri in the ECP, and set to "draw pattern", then applied another LUT Buddy effect after the clip, set to "read pattern", then told it to create a LUT.

Then I've a whole slew of controls set into that LUT that I can apply through dropping a LUT Buddy effect on a clip or adjustment layer, set to use that LUT I created with it, without even going into Lumetri.

Applying multiple instances of Lumetri to a clip to say work multiple HSL Secondaries (as I often do) can drag the computer way down slow. Throwing a couple of LUT Buddies onto a clip ... doesn't have near the same performance effect.

Neil

[Offbeat Bryce Productions]

I figured out how to save a Cube. When I import it the Curves section isn't the same as when I exported it. Is the Curves section supposed to be altered to what it was?

This is what the curves panel looks like after I imported the cube preset. It just reverts to default settings when i actually exported the cube as the curve white rolled off.

Also, Turning on High Dynamic Range which turns off the luts seems to fix the limitation as well.

s