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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Dragon Color science emulate film?

Gavin
if you actually read you will see that i wrote emulation emulation (AKA to turn digital images into filmic looking images ) .

print emulation used for a real print emulation (AKA the real use for it so printing on film ) is another thing and was certainly not the scope of the discussion .

this was about the creative way to get a filmic look
g
 
i think you gave a very accurate answer to the exact question and you're absolutely correct on all points. but i think that's beside the point. my point was to reply to the spirit of the question, which i interpreted and take to mean as, in reference to the rest of the thread, in simplistic terms for a non-colorist - do colorists use print-emulations luts for look-creation? i do not and i do think quite a few colorists go 'from scratch' although there may be numerous exceptions and i know of some and respect their process. custom/stock luts are really good for emulation... whatever works.

you're right that everyone has a starting point and there's absolutely nothing wrong with always using a certain one that you're familiar with or whatever is best for the look you're going for whether it's 'under the hood, automatic, or a custom lut. who cares? whatever works.

btw... who's making projection prints here that doesn't know all about this stuff?

i always appreciate your thoughtfulness and willingness to share knowledge, but i do think this is overcomplicating things when they need to be oversimplified (in this case) for the sake of plain discussion - may be the only time i ever say that, so i hope somebody's taking notes.

https://www.youtube.com/watch?v=x2YQJsbbWNA

now, back to more important questions - like is there a life-force outside our galaxy - which i'm pretty sure was where the op ultimately had in mind for the direction of this thread ;)
 
Gabriele Turchi said:
Gavin
if you actually read you will see that i wrote emulation emulation (AKA to turn digital images into filmic looking images ) .
Click to expand...

I would argue that the Arri Alexa default color profile is a film emulation LUT (or at least DPs seem to think so). So everyone who shoots Alexa is using a film emulation LUT. It's definitely more of a film emulation LUT than a video LUT. It's designed to be a starting comfortable for film DPs and colorists.

People are still trying to make some sort of distinction between default LUTs that ship with cameras and 3rd party LUTs. If your camera ships with a filmic LUT like Alexa then colorists are using a film emulation LUT (unaware). I would argue that the largest problem with RED today is that its default LUT isn't emulating film as closely as Arri.
 
paulherrin said:
i think you gave a very accurate answer to the exact question and you're absolutely correct on all points. but i think that's beside the point. my point was to reply to the spirit of the question, which i interpreted and take to mean as, in reference to the rest of the thread, in simplistic terms for a non-colorist - do colorists use print-emulations luts for look-creation? i do not and i do think quite a few colorists go 'from scratch' although there may be numerous exceptions and i know of some and respect their process.
Click to expand...
It's a complicated question. When we do film outs in color correction, we do have to go through a calibration process with the lab and the specific emulsion being used so that we know what we see in digital projection will more or less be extremely close to a film print that hits LAD AIMS density (i.e., a good print). Input LUTs, Display LUTs, and Output LUTs are all different. This is becoming less important in an all-digital world.

You also can't be a good commercial colorist with clients if you don't have a few dozen looks you can drop in very quickly just as a demo to give clients different options. But those are looks -- not LUTs per se. It's a buzzword and a gimmick, but I'm not saying they're worthless gimmicks, only that they're not panaceas that always work.

LUTs are very precise mathematical computations that take material shot in a specific color space and optimize it for a different color space. LOG -> LIN is a very standard LUT that many people use. (Ditto with RedColor 3 and RedGamma 3, which are very well-designed for looking at Epic footage in Rec709.) It mainly just gets the material in a good starting space. It's not unusual to drop in the LUT in an early layer or node (or even in the config), then do another correction on top of that to take it to a better place -- say, popping the contrast and providing blacker blacks -- and then use additional nodes for style and helping out the actors.

I don't think so-called "print LUTs" really do anything but provide one version of what somebody thinks a piece of film will look like. The problem I found, even going back to using Kodak's original 3D LUTs in 2002, is that it's kind of arbitrary and it's all very dependent on the look of the raw material. There's also lots and lots of tweaking room. In short, there are no easy ways to a solution. I would say that, given enough time, you could probably match 99% of a so-called look LUT with custom curves and a reasonable correction (log or lin). It just takes skill.
 
Gavin Greenwalt said:
I would argue that the Arri Alexa default color profile is a film emulation LUT (or at least DPs seem to think so). So everyone who shoots Alexa is using a film emulation LUT.
Click to expand...
Actually, I think the stock Arri LUT grinds the footage quite a bit. I usually wind up bypassing it and just using some custom settings, depending on the cinematographer's particular style. On a recent project, both of us felt the Arri LUT was just too dark, so we duplicated the same look and bumped it up about 25%, and he was perfectly happy with it for the whole shoot. I wasn't about to tell him to open up, because they were already pretty much wide open and on a tight schedule, so we made do with what we had and it was fine.

If there's anything I learned from two years at Kodak (Cinesite/Hollywood) and many, many years at Technicolor, it's that LUTs can be almost anything you want them to be. (This has been referred to as the "LUT of the Month Club.") It never hurts to look at what the manufacturer initially suggests, but I have yet to see a project where a colorist doesn't tweak the living hell out of the LUTs or bypasses them entirely and does it manually. Anything works as long as the DP and director are happy and the material looks good in the room.
 
you're right, didn't mean to bash presets, looks, etc. these are good approximations and time-savers. i doubt i'll ever worry about a film-out but who knows, luckily i've never had to color a commercial, so i don't have to know whether i'm good at it or not ;)

i'm thinking more the philosophy of plop/done that kind of gets promoted and i think it's a fad worth warning about, especially around self-proclaimed 'future-proofers'. course i'll say it again, however you get to where you're happy with it. i'll also say that in all honesty 'it don't matter what you look like' cause there's a lot more to visual storytelling than technical and subtle (this is relative, what we see as huge is usually very slight for average joe, whoever that is) qualities of an image that most folks won't notice, not consciously.

at the same time, it is a visual art and spectacle... i'm a big believer in the way such subtle details (or obviously, drastic stylization) of light and color and texture play into the experience with different levels of awareness (including unawareness). that comes from the dance that a colorist does with the cinematographer, gaffer/grips, directors, producers, designers, and the rest of the creative team. i love that we have the compartmentalization/solos down, but i'd really love to see more true collaboration and i do think minimizing the distance (virtual, physical, and philosophical) between production and post is the way to move. you cain't fix stupid in post...
 
Gavin Greenwalt said:
I would argue that the Arri Alexa default color profile is a film emulation LUT (or at least DPs seem to think so). So everyone who shoots Alexa is using a film emulation LUT. It's definitely more of a film emulation LUT than a video LUT. It's designed to be a starting comfortable for film DPs and colorists.

People are still trying to make some sort of distinction between default LUTs that ship with cameras and 3rd party LUTs. If your camera ships with a filmic LUT like Alexa then colorists are using a film emulation LUT (unaware). I would argue that the largest problem with RED today is that its default LUT isn't emulating film as closely as Arri.
Click to expand...

Yes!


Hans
 
Marc Wielage said:
Actually, I think the stock Arri LUT grinds the footage quite a bit. I usually wind up bypassing it and just using some custom settings, depending on the cinematographer's particular style. On a recent project, both of us felt the Arri LUT was just too dark, so we duplicated the same look and bumped it up about 25%, and he was perfectly happy with it for the whole shoot. I wasn't about to tell him to open up, because they were already pretty much wide open and on a tight schedule, so we made do with what we had and it was fine.
Click to expand...

In that instance were you bypassing the LogC-> XXXX lut (aka their website's LUT generator) or working from the RAW? What I meant to say was that the calibration of the sensor to output any image at all is in of itself a LUT with a filmic color profile. As to Arri's LUTs (From its LUT generator)... I feel your pain I, especially hate the logC -> lin ones which never seem to work and always clip data. I still don't know why Arri is pushing a non-standard log curve. It just creates endless frustration.
 
Gavin Greenwalt said:
Everyone uses LUTs. REDGamm3 is a LUT. It takes the linear output from RED and maps it to something approximating sRGB. If you're working in sRGB (video) space then there is a LUT behind the scenes converting it to linear for output from the LCD (LCDs as is real life in linear). If you're working in log space then there is a log -> sRGB framebuffer LUT-> linear LUT (the last bit somewhere in the monitor). If you're working directly in linear colorspace then your OS wants the framebuffer in sRGB space so there'll be a linear -> sRGB LUT (Which is then by your monitor converted back to linear). If you are planning on outputting to film you should have a printing emulation LUT on your viewer. If you're working in ACES space there is an ACES -> sRGB lut for your framebuffer.

At the very least though there is a RAW -> REDColor 3DLUT somewhere in your pipeline if you shoot red. RED calls it the "SDK" but the "SDK" is ultimately a decryption algorithm, tied to a JPEG2000 reader + audio sauce, tied to a debayer algorithm tied to a 3DLUT.

To quote Yoda, LUTs are all around us... they surround us, they penetrate us... they... bind the universe together?
Click to expand...


That's a lotta LUTs.




While on LUTs....there are also perceptive and cognitive LUTs.
Both vary on person's subjective (internal) and environmental (external) factors, leading to a very relative perception and impression of a "film" look.

One cognitive LUT related to this repeating subject on Reduser often seems to lead to expectations of a digital equivalent of a magic pill to easily make everyone's footage look as the one on the big screen coming from an ASC member and his post colleague - colorist, or any other skilled craftsmen who through collaborative effort made possible the overall impression of the image.

This particular LUT is the child of train of thought which is preconditioned with another perceptive LUT, whose color science tones the impression that the image seen on the cinema screen is mostly due to the excellence of box of electronics sitting on three sticks pointed at something and all by itself giving birth to a creation pleasing to humans. The LUT whose color primaries are offset by the emotional toning of the observer, which is the human desire to possess the value experienced outside, while attempting to avoid the effort of investing the equivalent amount of work inside.

One of the notions which might help in designing a different and potentially more beneficial perceptive LUT is the notion that the material coming from film - or Alexa is rarely directly and/or solely graded by the same person who shot it.

Gavin Greenwalt said:
It depends on the LUT. A RC3 -> Vision3 LUT gives you Vision3 as a starting point. Lots of DPs love Vision 3. Where you from there for emotion and color and tone is still up to you.
Click to expand...

Comment was related to the context of an inexperienced person using a LUT, not knowing what it actually does, especially for a different purpose. The achievable range and directions of picture shaping are greatly dependent on what a specific image transform does to that specific image. It also affects the intent, the subjective part.



The abbreviation "LUT" was used 10 times in this post. Without the quoted part.
Used for specific material. Apply with caution.
 
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Gavin Greenwalt said:
In that instance were you bypassing the LogC-> XXXX lut (aka their website's LUT generator) or working from the RAW? What I meant to say was that the calibration of the sensor to output any image at all is in of itself a LUT with a filmic color profile. As to Arri's LUTs (From its LUT generator)... I feel your pain I, especially hate the logC -> lin ones which never seem to work and always clip data. I still don't know why Arri is pushing a non-standard log curve. It just creates endless frustration.
Click to expand...
I don't hate it necessarily, but I also feel it clips a little too early. I have my own LUT that I drop in as the first layer correction to go from LogC -> Rec709, using a combination of curves, log corrections, and a chroma boost. Based on charts, this is a better starting point than the stock Arri LUT.
 
not to derail this thread (might start my own instead)

but, what do you guys think of Red and rec2020? is dragon color space optimized for rec709 or rec2020? cuz if its 709 (which from my understanding is what red color gamma 1,2, and 3 is supposed to emulate) then they very well may want to work on the rec2020 version now as well. it'd be nice to have some options for deliverables as we bridge the gap so to speak between color space standards...

i wonder in a rec2020 world where we stand on alexa vs red in that space? i don't even have anything yet that runs rec2020
 
Brian Merlen said:
i wonder in a rec2020 world where we stand on alexa vs red in that space?
Click to expand...

Rec. 2020 world is still in the works and for the camera user there is little benefit in bothering with it at this point.
 
David Battistella said:
Try the alchemy tools in RCX. Your render times will skyrocket it's not neat video t but it could help..


battistella
Click to expand...

There's no noise reduction in Alchemy is there? Neat isn't a tonemapper like alchemy it's a wavelet/interframe noise reduction algorithm.
 
Paulo Emílio said:
Neat Video OFX plug in on REDCINE-X would be amazing!
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This and support for exporting to VFW codecs on windows. Quicktime on Windows is just awful.
Some form of direct integration with Adobe Media Encoder would be fine too. ;)
 
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