Working With LUTs

A member of DVXuser posted a question about LUT workflow and this was my answer.

Published Categorized as Personal
Oz2

A member of DVXuser posted a question about LUT workflow and this was my answer.

My basic workflow is prep, shoot, ingest, edit, mix (sound), color (where you apply the LUT and do your coloring), deliver and pray. It is more complicated than that, but I want to keep things simple. Well, actually…

First, what is a LUT? A ‘Look Up Table’ is a way of ascribing to a digital image the way colors are mapped or those values are assigned. They can describe how ‘yellow’ orange is, for example. Colors evoke a mood and it is part of the psychology that goes into setting the tone of a show using the visual language of that show which is a combination of production design, lighting, composition, blocking (both talent and camera) and stage direction, performance (including timing, expression and blocking), even goes as deep as the ‘flow’ of the show; i.e., where the cuts go and how they relate to the performance and the camera moves, etc…since those should be planned and shot for on-the-day. This whole ‘fix it in post’ thing is a crutch, but I digress. Also, ‘flow’ is part of ‘tone’ and is different from ‘workflow’.

Speaking of ‘workflow’: there are a lot of different ways to go about this and answers are generally subjective depending on a bunch of parameters.

Basically, you need to find a workflow you prefer and one that keeps your clients happy. Some folk like the look of logarithmic footage without processing of any kind. Other folk grade it so much it looks like terrible, cheap consumer video. Most of the professional stuff you see in broadcast media and movie theaters are graded in some way. Only occasionally do you come across some old-school film peeps who create the look both on the day via filmstock, filters and gels, and in the lab, avoiding a DI process altogether. That’s ‘Digital Intermediate’, by the way: the phase the edited footage goes through the coloring process, usually with the colorist in some combination with the show’s DP, producer or director. ‘Digital’ because it’s done on computer, and ‘Intermediate’ because it is the process between editing and duping – ‘duplication’…lots of stuff newbies need to look up.

The basic workflow stems from the idea that you generally shoot something with the intent of it looking a certain way which is planned between the script-writing phase and the production phase; usually to help the visual language of a show (read: movies, music videos, TV series with any number of different styles or genres on display) evoke an emotional response from its intended audience. The visual language of the show as a whole, or sequences within the show, or scenes within the sequences within the show as a whole, or individual shots within the scenes within the sequences within the show as a whole, can be treated visually different from each other, but generally a show develops its basic look and style within its first few seconds to ground the audience and establish something we like to call ‘tone’. Establishing the show’s tone goes a long way to help suspend the audience’s disbelief and allow them to either enjoy your show or change the channel. That is why you can not start watching a movie from the middle and why comedies are generally broadly lit with saturated colors and dramas usually have a lot of shadows with muted colors.

Sometimes you want to break up sections of your show (like dramatic acts or sequences or scenes) with different palettes but the general tone of a show should be consistent throughout. I shall use the classic fantasy adventure film “The Empire Strikes Back” as an example. It starts with a cold environment with lots of whites and blues; the good guys have bits of orange intercut with the militaristic bad guys’ grays and deep blacks. The second act has deep greens, reds and oranges, with the third act becoming much colder, all intercut with those grays and deep blacks of the bad guys. All of it has a slightly cool look with desaturated highlights and midtones with shadows that like to dip into blue. It is a generally blue-ish movie: cold and subjective, which aid the film’s anxious tone…but without becoming depressing. When our heroes finally admit their love for one another, the camera is closer and the orange and reds of the room penetrate the scene. “Empire” is the most dramatic of the Star Wars movies, and a terrific film by itself (how I prefer it) which I encourage you to watch with the sound muted. In fact, you need to start watching everything with muted sound. If you can’t follow along, then it’s not good storytelling.

You have to learn why things work on a starship.

Captain James T. Kirk

Once you have the tone in mind and have established what sections should look like what without betraying that tone you want the show to establish, then you go about testing different films, cameras, lenses, filters, lights, gobos and intermediate processes (where LUTs come in) along with production design such as wardrobe, the colors of the sets, makeup, props, etc…and combinations of all of that – with talent, or at least stand-ins – to ensure the tone you’re going for will be served. Or, you watch a movie or two and decide that you want your movie to look like someone else’s movie, but better-er-er. Whatever. Point is: come up with the show’s tone before you shoot.

Nowadays it is all very simple because you can have video reference monitors with the ability to import LUTs so you can pretty much see what the final show will sorta look like on the day. You generally light with a style that considers the tone and look and feel of the show and the LUT is a part of that. Seeing it on the day in the monitor is nice but should not be the only thing. It is merely a guide for everyone else except the DP who should know better and understand that, despite the base LUT, the show will still need to be properly graded and shots individually tweaked or corrected.

There is this neat vignette on the collector’s edition of David Fincher’s excellent “Seven” where his go-to colorist shows examples of coloring that special edition of the film for home video release in what film critic Jeff Shannon described as “a fascinating exploration of the audio remixing and video remastering process, demonstrating the subtleties of digital color and tone manipulation.” It uses the final scene as an example: shots done days or weeks apart and show with various lenses and lighting conditions all need to match so they look like the scene takes place all in the same place at the same time. That’s what coloring is all about. A LUT will help you get there, but you still need to have an understanding of what’s going on outside.

A LUT is simply another tool in the box.

What I am saying is you can not shoot something and then apply a LUT willy-nilly like it is a magic potion that will make everything look legit. You have to plan, you have to shoot for that plan and then execute the plan. You marry into it…even if it was the wrong decision; you commit. Because you would rather spend two years making a movie than two hours watching one. I digress, and no it is not a simple answer at all. A LUT is simply another tool in the box. Logarithmic profiles are another tool. Variable frame rates, DCI 4K and servo zooms are other tools. They all work together to serve the show – whatever it is – whatever message you are trying to say, story you are trying to tell or feeling you want to make the audience feel.
They are only tools and you need to learn them.

Once you know the rules, then you can start breaking them and that is where the fun begins. That is when you can tell a story backwards or use visual metaphors or whatever. That is why experimental films are usually shot by amateurs simply learning their craft, whereas when an established filmmaker creates an experimental film they are usually more coherent. They are better at using their tools to do what they want them to do; build the house that they want to build. Then we can prattle on about foundations like concept, idea, story, script, etc.

It is true the best LUT in the world can not fix broken footage, but also the best footage in the world can not fix a bad performance, bad direction or a bad script. They are all pieces to this enormous puzzle…even when you are just shooting a few interviews, stuff needs to be considered. You need good sound, good light, good composition, good answers, good questions, a motive. You do not simply show up and shoot without looking at the location and deciding whether to use the windows or not, the desk or not, that lamp on the table or not. Movies do the same thing except they consider that on paper and then design and build their sets with the intention of it all serving the style and tone of the movie that helps tell the story in the most appropriate way. That is what it is all about: being appropriate in regard to how the story is told.

That is what it is all about: being appropriate in regard to how the story is told.

Getting back to it: you can certainly ingest your footage, apply your LUT and color, export the graded footage and import that footage into your editor and go from there. Or, you can round-trip by editing the footage, exporting the timeline into a grading software where you do the coloring and then take that back into the editor to tweak and export deliverables. Or, have a one-app solution where you can both edit and color at once on the same timeline in the same app. Apple’s Final Cut Pro and Blackmagic Design’s DaVinci Resolve come to mind.

I use FCPX 10.2.3 which does not natively support Panasonic’s V-log (Varicam) or V-log L (DVX200, GH4) at this time, though you may use another flavor of log-to-REC.709 it does support, such as Canon’s C-log. Regardless, you still need to process your footage. For more precise controls there are a number of plug-ins available to grant FCPX the ability to assign LUTs and subsequently correct and grade footage. I use LUT Utility with FCPX’s Color, or Color Finale Pro from Color Grading Central.