REDLogFILM > Rec.709 LUT - Anyone have one? Made one? Graeme?

[Pablo Moreno]

Unless Pablo works for Red, it's not gonna cut it.

I would very much like an official white paper from RED about working w RedlogFilm in a professional environment, meaning where you have several post houses collaborating, and using
official LUTS (like we do with Arri and Sony...).


Redlogfilm LUT's should be available either as download on RED.com or be provided by RED to the relevant software companies, so you have
the official LUT's that can be selected.


For feature work or High end commercials, where post takes place immediately and in several countries at the same time - It is not a solution having well meaning redusers making their LUTS... and sharing them...
and NO you don't have the time to work out a pipeline for each job for each post house.... which is why "official" is the key word.

Guys, you are going to have to get out of Red heaven for a second, and explore other universes.
Red people are not the only ones who have all the answers here.


In fact, I already have, what I should call, an "unofficial Redcolor 4" almost ready, that corrects skin tones and everything. Hard to believe?, well, also, I managed to change the color matrix from Redcolor3 to a real Rec709, but still staying in the RedlogFilm gamma, all with a simple LUT, how about that?..

But certainly you're not going to believe me, because my name is not Graeme Nattress..

Anyway, stay tuned..

 

[Bob Gundu]

Intrigued... Please show and tell when ready!

Guys, you are going to have to get out of Red heaven for a second, and explore other universes.
Red people are not the only ones who have all the answers here.


In fact, I already have, what I should call, an "unofficial Redcolor 4" almost ready, that corrects skin tones and everything. Hard to believe?, well, also, I managed to change the color matrix from Redcolor3 to a real Rec709, but still staying in the RedlogFilm gamma, all with a simple LUT, how about that?..

But certainly you're not going to believe me, because my name is not Graeme Nattress..

Anyway, stay tuned..

 

[George A.]

Guys, you are going to have to get out of Red heaven for a second, and explore other universes.
Red people are not the only ones who have all the answers here.


In fact, I already have, what I should call, an "unofficial Redcolor 4" almost ready, that corrects skin tones and everything. Hard to believe?, well, also, I managed to change the color matrix from Redcolor3 to a real Rec709, but still staying in the RedlogFilm gamma, all with a simple LUT, how about that?..

But certainly you're not going to believe me, because my name is not Graeme Nattress..

Anyway, stay tuned..

Looking forward to seeing what you cooked up, Pablo...

 

[Sidney L. Plaut]

im still looking forward to a LUT from RED I can load into for instance Davinci...

Sony... Canon and Arri all have one...

 

[Luis Otero]

Any update, Pablo?

Any update, Pablo?

...In fact, I already have, what I should call, an "unofficial Redcolor 4" almost ready, that corrects skin tones and everything. Hard to believe?, well, also, I managed to change the color matrix from Redcolor3 to a real Rec709, but still staying in the RedlogFilm gamma, all with a simple LUT, how about that?..

But certainly you're not going to believe me, because my name is not Graeme Nattress..

Anyway, stay tuned..

Pablo,

Any update on this effort, and any resulting LUT to achieve the "real Rec.709"?

 

[Joel Arvidsson]

Whats been cooking Pablo? Any still grabs?

 

[Gavin Greenwalt]

I find it absolutely fascinating, that we even need to have this conversation. How much time had passed from the introduction of RFL? A couple of years? And yet, no official response from Red on a proper LUT. WTF!!!??? They introduced RLF, stated, that it's perfectly adheres to Cineon standard and for the rest you're on your own. Come up with your own LUT for all iterations of RLF/RLF2/RLF3 legal and full for ADSK, Resolve, Nucoda, FilmLight, Nuke, AE and on and on and on. So, people in post chain start using third party solutions, so nothing matches between users and no one at Red cares. How difficult would be for Red to release an official LUT for main software platforms, so everyone operates on the same plane? LUT generator would be great too.

RED doesn't need a REDLogFilm LUT. It's just cineon. Every single decent editing, compositing, playback and grading program on earth has the LUT built in. The reason Arri has to provide a LUT generator is because if you record to different ISOs you have to have a separate LUT for every ISO. Which is to say the Alexa approach is #()@ mental. Alexa also by default bakes in its equivalent of RG3. So you need a full suite of custom ISOs based on every combination of Gamma, ISO and gain.

Log -> Linear though on RED works perfectly because they don't bake in the ISO or anything to RLF.

Is everyone here assuming that REDGamma is REC709? Because that's a whole different bag of worms. But if you ask nicely RED will give you the LUT. Not sure why it's not publicly available. It should be.

 

[Gavin Greenwalt]

Here is a Cin->Rec709 LUT in the 2 most popular flavors.

 

[jake blackstone]

RED doesn't need a REDLogFilm LUT. It's just cineon. Every single decent editing, compositing, playback and grading program on earth has the LUT built in. The reason Arri has to provide a LUT generator is because if you record to different ISOs you have to have a separate LUT for every ISO. Which is to say the Alexa approach is #()@ mental. Alexa also by default bakes in its equivalent of RG3. So you need a full suite of custom ISOs based on every combination of Gamma, ISO and gain.

Log -> Linear though on RED works perfectly because they don't bake in the ISO or anything to RLF.

Is everyone here assuming that REDGamma is REC709? Because that's a whole different bag of worms. But if you ask nicely RED will give you the LUT. Not sure why it's not publicly available. It should be.

Yes, Red can claim that RLF is a standard Cineon until they blue in the face, but it still doesn't change the fact, the most popular grading solution, like Resolve doesn't include one. Majority of users just use supplied AlexaV3_709_LogC2Video. I find that unacceptable. I also find it funny, that different people claim "official" Cineon LUT for RLF and somehow we all should trust that LUT. Red should just release an official, Red blessed RLF LUT without the need to "ask nicely" and move on to other more pressing issues.

 

[Paul Russell]

this is a great thread. I'd just like to thank you guys for being so generous and open with your experience and LUTs

 

[Gavin Greenwalt]

I also find it funny, that different people claim "official" Cineon LUT for RLF and somehow we all should trust that LUT. Red should just release an official, Red blessed RLF LUT without the need to "ask nicely" and move on to other more pressing issues.

Red isn't "claiming" anything until they are blue in the face. Anyone can verify it for themselves. Export a Linear image in EXR and then one in RLF and apply a standardized Log-to-linear LUT. Now compare. They'll be exactly the same.

Of course lots of people claim "official" Cineon LUTs... they're all probably exactly the same! Cineon is a mathematically consistent SMPTE standardized equation. If you take a RLF image, apply a reverse Cineon curve it comes out perfectly exact to RED Linear. Why would RED create an "official" LUT for a standard that has been around since the early 90s. It's not some new fangled proprietary RED specific LUT, it's industry wide and more than 20 years old.

As to why Black Magic doesn't have an industry standard curve? No idea. You would need to take it up with them. Maybe the free version doesn't have a curve intended to work with film originated material. Maybe they assume your monitor will just be calibrated for Rec709 so you'll want to grade in LOG space as was the traditional film workflow. They have several curves to get you into Cineon. So if you want to grade in LOG space... RLF is already there. They saved you a step.

 

[Gavin Greenwalt]

Also here is a display LUT so that you can actually properly monitor Rec709 footage on an sRGB calibrated monitor.

 

[Nook Kim]

Totally agree. IMO it's another FU to post people by Red. First, you need to spend $5k on RR, which by the way had no reduction in price in over three years, unlike their cameras. And no assistance at all with proper LUT for use with RedLogFilm, other than " just use standard Cineon LUT". Compare this approach with Arri, providing proper LUT at no charge to everyone for any type of software. So, now everyone uses Arri Alexa LUT for RedLogFilm and then everyone wonders why Red skin tones are funky And Red still can't understand why they're disliked by the post community...

Very old post to quote, but worth Red's attention.

 

[Nook Kim]

I find it absolutely fascinating, that we even need to have this conversation. How much time had passed from the introduction of RFL? A couple of years? And yet, no official response from Red on a proper LUT. WTF!!!??? They introduced RLF, stated, that it's perfectly adheres to Cineon standard and for the rest you're on your own. Come up with your own LUT for all iterations of RLF/RLF2/RLF3 legal and full for ADSK, Resolve, Nucoda, FilmLight, Nuke, AE and on and on and on. So, people in post chain start using third party solutions, so nothing matches between users and no one at Red cares. How difficult would be for Red to release an official LUT for main software platforms, so everyone operates on the same plane? LUT generator would be great too.

+ the number of Dragon pixels

 

[Luis Otero]

Gavin,

I agree with most of your statements. We always do our grading using RLF. However, before the RC3 iteration was available, what we tested for film-out purpose as an 100% equivalent of a Cineon file was the combination of RLF + RC2. It is a fact that RC2 and RC3 render different color image profiles. So, depending on the pair you used (RLF + RC2 or RLF + RC3), the outcome LUT is different.

So, which combo was the one used to develop the LUTs that you are offering? Also, what objective testing was used to confirm that such LUTs render Rec.709 color space colorimetry?

Please advise,

 

[Björn Benckert]

So if red refuse who can do the cross converter from r3d redgamma2_redlogfilm and redgamma3_redlogfilm to just about anything and also corresponding / negative luts going back and such. My programer resigned and will be working in the gaming industry from next week on so I can not do it

 

[jake blackstone]

As to why Black Magic doesn't have an industry standard curve? No idea. You would need to take it up with them. Maybe the free version doesn't have a curve intended to work with film originated material. Maybe they assume your monitor will just be calibrated for Rec709 so you'll want to grade in LOG space as was the traditional film workflow. They have several curves to get you into Cineon. So if you want to grade in LOG space... RLF is already there. They saved you a step.

It is not Blackmagic's responsibility to provide a proper LUT for a given camera. BTW, included LUTs in free and paid versions of Resolve are the same. The same goes for the the need for IDT, that is to be used for ACES workflow. Oh yeah, I forgot, Red doesn't recommend using ACES with Red material
Why should BM spend on R&D, that should clearly be provided by the camera manufacturers? And I don't see why end users a forced to scour the Internet for proper Cineon curle LUT to be used with their choice of color grading or compositing software.

 

[Sidney L. Plaut]

So I must conclude in this several months old thread. That the solution is merely to ask RED politely. So:

I am hereby officially asking very politely for RED to supply an official LUT - for use in Resolve and other major software and Compositing software.

I love RedLOGFilm. I would like to have the option of choosing an official LUT. Like I can with the competitions camera LUT's.
Meaning I will transcode to Redlogfilm but monitor and grade in Rec709 with the hopefully new "REDLut".

 

[Gavin Greenwalt]

Gavin,

I agree with most of your statements. We always do our grading using RLF. However, before the RC3 iteration was available, what we tested for film-out purpose as an 100% equivalent of a Cineon file was the combination of RLF + RC2. It is a fact that RC2 and RC3 render different color image profiles. So, depending on the pair you used (RLF + RC2 or RLF + RC3), the outcome LUT is different.

RED Color will affect the output, but REDColor is the colorspace not the gamma. I don't believe Arri releases any colorspace LUTs either, just luminance (gamma) LUTs. I'm not even sure it would be possible to go from RC3 -> RC2 or vice versa since both are the product of a 3D LUT on top of I think CameraRGB. 3D LUTs often aren't reversible since you could target 2 different source colors to the same destination color at which point how do you arbitrarily decide which output color goes to which input color. Most 1D LUTs (Although not necessarily all) are a 1:1 function and can be easily reversed. Especially something like Cineon (RLF) which was created with that in mind.

So, which combo was the one used to develop the LUTs that you are offering? Also, what objective testing was used to confirm that such LUTs render Rec.709 color space colorimetry?

Please advise,

It doesn't matter what footage you use. I didn't develop the LUTs even using RED footage. It's a consistent Mathematical equation like Gamma. For instance gamma is LinearPixelColor ^ (1/gamma) = CorrectedPixelColor. And the inverse is CorrectedPixelColor ^ (gamma) = LinearPixelColor. You don't have to know anything about the source material to apply the correct gamma correction. I just used Nuke's colorspace tools which in previous testing have always matched when I compare to RED and other company's DPX/Cineon and Rec709 outputs. I'll check later in the morning with those exact LUTs to make sure I didn't botch anything, but I did a quick check in Davinci last night to make sure they looked right and were openable in Davinci and they looked correct.
+

 

[Mike Nagel]

For instance gamma is LinearPixelColor ^ (1/gamma) = CorrectedPixelColor. And the inverse is CorrectedPixelColor ^ (gamma) = LinearPixelColor. You don't have to know anything about the source material to apply the correct gamma correction. I just used Nuke's colorspace tools
+

that equation is not fully correct AFAIK, as the Rec709 spec includes a fixed offset... does Nuke's colorspace tool incorporate that ?

Thanks.

- M