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The primary purpose of the 2383 print emulation LUT isn’t to create a film look, it’s to work within a color space/gamut that works for both a DCP and a film-out so the movie would look the same in both versions. It’s less of an issue today with so few film-outs being done.
A 2383 print emulation is a very different look to for example arri’s rec709 LUT. A 2383 print film look is synonymous with the look of projected film, hence for example Steve Yedlin went to great lengths to model it for his Alexa film emulation which he has used on all his recent digitally shot films and is loaded into his camera via a LUT he built. Steve describes his 2383 model as the ‘target look’, and what represents ‘film’ most to him and much more so than camera negative. There are also many other cinematographers who use a film model in camera via a LUT that includes a 2383 print film model. The effect of a 2383 model upon colour characteristics and contrast is significant. These characteristics are the reason why Fotokem offer a scan back service printing digital files to 2383 and scanning it back – specifically for the aesthetically pleasing attributes that the film print imparts.
I don’t think you can separate a 2383 print emulation from the ‘look’ of film. Granted it is just one film look but a significant one none the less. Rogers LUT incorporates a 2383 model as JZ describes. If you were to switch out this log to display part of the LUT for arri’s log to display 709 LUT there would be big differences, and not very pleasant ones.
Thanks for the background info. Fwiw, I use a scene referred 2383 Print Film LUT (free from Lutify) in color managed Davinci Resolve with good success. Contrast might be too high for cameras with less dynamic range than Alexa though.
I would note that there is a big difference between applying a print LUT in post to shooting through a print LUT on set as Roger and many other cinematographers do. You will light differently and also will be able to produce an image that is much closer to the intention if the show LUT is set before shooting. I don’t think the contrast of the LUT has too much bearing on what camera is used. If anything, using a more contrasty LUT on set will give you MORE information in post becuase you’ll put more fill light into shadows and less into highlights. Shooting through a flat LUT will render the opposite ie less information in the shadows. There are so many benefits to establishing a LUT before shooting and then shooting through it, not least that more of the cinematographers intention will be in the dailies / offline edit that the director etc get used to.
As JZ described. When True Grit shifted from film projection to digital display JZ and Arri profiled the 2383 print. This was the basis for the LUT when moving to Alexa, with an additional step of converting the Alexa output to better represent a negative before going through the profiled 2383 print.
I would imagine that when Roger tweaked the LUT it was contrast / saturation adjustments being made underneath the print film profile JZ had previously developed ie the large majority of the colour and contrast reproduction of the LUT was already set. This final adjustment would then be baked into the final LUT which goes into production (loaded into monitors or potentially into the camera itself if the camera is capable of 33x 3D LUTS, which is the case for cameras from Alexa SXT / Amira onwards).
The work and skill that goes into building a LUT like Rogers seems to be extremely underestimated.
Roger’s LUT won’t look anything like arri’s rec709 LUT because Rogers LUT is built from a print film data set and also incorporates an Alexa to film negative transform, as per Joachim Zell’s description. It took weeks to create the LUT.
If you went into a DI suite and applied arri’s standard 709 LUT then tweaked with contrast and saturation or other standard colour corrector tools you wouldn’t get close to Roger’s in terms of the colour behaviour. For example highly saturated colours becoming dark and rich with a film like subtractive saturation. Take a look at the greens you get out of arri 709 – bright and garish vs the greens you’ll see in Rogers work that have far more of the print film yellow character and are less saturated and bright. Creating a LUT like Roger’s isn’t easy to do in the slightest, for a start you have to have a large film data set, a very complex undertaking. Then you have to develop custom tools for clean colour manipulation, tools which are not available in a standard color corrector.
Roger’s LUT isn’t like any other, simply because LUT’s vary wildly, are built in thousands of different ways, based on very different data sets, and built by skilled and non skilled people. Each LUT has its own personality and characteristics. Some are simple, but the complex and smooth film based LUTS like Rogers, built on rich data sets are rarely available to the public and for good reason. These types of LUTS are usually built by colour scientists at post facilities or bespoke for a project – for example Kodak colour scientist Mitch Bogdanowicz who built the LUT for Joker – which emulated an out of production film stock.
When Roger tweaked his LUT in a DI suite, as Joachim Zell who built the LUT describes – a huge amount of work to build the LUT would already have taken place. The tweaking of saturation and contrast at this point would represent small changes to an already complex model that had been previously built.
Whilst a LUT certainly is just a part of a look, it’s certainly still a significant part because it essentially represents a digital ‘film stock’, building in contrast, colour crossover (eg blue blacks warm highlights), hue v hue, saturation and complex non linear colour characteristics (eg bright garish colours becoming darker). These characteristics can have a huge impact on an image, not to mention on how you light. Rogers contrast curve will have quite a bit more contrast than Arri’s 709 K1S1 LUT for example because it is based on a print film data set. One result of this is that when lighting you will inevitably put more light into your shadows than you would if monitoring through Arri’s LUT. Steve Yedlin talks about this quite a bit also. Steve has his own model built using custom tools from a 5219 printed to 2383 data set.
