- Juan I. Cabrera
Beyond the looks of StartUp: LightBender’s favorite HDR workflow techniques
We were super excited to see that the StartUp series, one of our all-time favorite projects, is now available on Netflix. This has brought up so many great memories that we wanted to share some HDR workflow tips and tricks that enabled us to work faster, smarter, and deliver a great-looking show.
Shooting in high resolutions, VFX-heavy shots, tight schedules, and several different deliveries (including HDR) are some of the most common challenges when creating episodic features that comply with the major OTT’s delivery standards. However, with the right mindset, meticulous preparation, and keeping in mind the following five points, you will avoid some of the unnecessary stress and exceed expectations.
Let’s crack on!
Don’t clip your signal
Let’s start with the shooting. One of the most common and straightforward recommendations for exposure that will work well with SDR and HDR versions is not clipping your signal. Make sure you capture the full latitude of light, because there is nothing that looks worse in HDR than a full blown-out sky! Providing all the information to your colorists will give you way better options when it comes to grading. HDR is about texture, even in the highlights. So the more you protect them, the better. HDR is a process that happens 100% in post, so you need the best possible options from the get-go to avoid getting yourself in a bad corner later.
Besides the typical daytime exterior with a gorgeous sky, or shot with bright colorful features characteristic on HDR demos, many other scenarios can look absolutely beautiful in HDR. Here are a couple of examples:
Night shots with practical lights. Darker scenes with light sources create a really nice and colorful contrast, making the scenes feel more detailed and layered.
Shadowy shots with bright highlights: When you have a subject in the shade (or semi-shade) but still have some sunny spots, those spots really beam with life and light. They will absolutely FEEL like sunlight.
First SDR and then HDR
When designing the production and post-production workflow, the final delivery plays a crucial role, especially if you are dealing with high resolutions or different aspect ratios. In the case of StartUp aspect ratio was not an issue (the show is 16:9 throughout) but Sony wanted to ensure we had a full UHD workflow from beginning to end. So from the camera tests, to the conform, color, reviews, and outputs, everything was designed to be UHD as the prime format and all the other online and HD deliverables would be derived from that. In that regard, you have to do your numbers and make sure you allocate enough hard drive space and speed to allow everybody to work comfortably.
In the case of HDR, it depends on what color workflow you are going to follow. You can usually get better results and better collaboration when you start your work with the Rec709 version (without clipping the signal of course!) and then create the HDR after the show look has been approved. This has three advantages:
It allows people to work and visualize in a color space that is familiar to them, and it allows for more flexibility when it comes to viewing devices.
It helps ground the project’s look in a way that DP, director, producer, and studio are used to seeing… I’ve seen a few native HDR sessions where everybody starts second-guessing themselves, and at the end, the project suffers.
When you start the work on the HDR version, you already have a perfect reference for your Dolby Vision trim pass that everybody loves, so it really simplifies and speeds up the trim process.
HDR: Much more than just a brighter and more saturated SDR
Sometimes when people talk about HDR they just think about something brighter and more saturated than SDR, but in reality, the more dramatic change happens in the textures of some shots. Having a wider light and color range creates more differences between shadows and highlights, which in turn contributes to being able to see things more clearly, with more separation. The change doesn’t have to be super-dramatic for the audience to feel it… Some of the latest HDR shows don’t even reach very bright peaks for the most part, but just being able to go past the 100 nit limit of SDR adds so much more.
Think about HDR as a paint bucket. It’s a MUCH bigger bucket than an SDR bucket! But the fact that you have more capacity, doesn’t mean you have to use it all. It’s all about having the freedom to push it when pushing it helps the project aesthetically. You can still have your dark scenes with deep shadows and never go past the 100 nits. It’s all about what works best for the show, the scene, and the shot… And that’s why I feel so strongly about creating the Rec709 pass first. It gives a common ground for everybody to work on, without second-guessing or worrying. And then, when creating the HDR pass, everything becomes much more playful because the look is defined already.
How to save time (and money)?
My number one advice would be to start conforming as early as possible to maximize the time available for color. I understand this can be a difficult choice when you are working with certain platforms since re-conform and recovering color from one version to another might be challenging, but it really pays off in the end! In our case, we use SGO Mistika Ultima which, in my opinion, has the best conform tools and editorial flexibility available. We often design workflows on the premise that the show “will never lock” so we can both start color soon and give editorial as much time as possible to finesse the cut. This allows us to start discussing looks, spot potential issues, and start reviews earlier than anything else.
Another critical aspect that can save you a substantial amount of time is VFX handling, which leads us to our next point.
Take control of VFX!
If the show has VFXs, we export the plates and test the whole workflow to and from the VFX vendor as early as possible to spot potential issues. It’s important for the plates to be exported by the Color house since that’s the best way to guarantee color, format, and framing accuracy. Once exported, we deal with the shots in the color grading like everything else, so we can get ahead in color even if we don’t have the VFX shot back from the vendor. If all the color workflow is designed properly, once we get the VFX render, the color will match exactly. The shot might need some minor adjustment depending on how big the VFX has changed the nature of the shot, but overall the time spent in tweaking will be minimal.
The first part of the process, once we were getting the shots back, was to test the alpha channel. We would bring the shots into a timeline and push the color in several directions inside and outside the mask, to ensure it was not breaking, losing quality, or artifacting. If the test was successful, the shots were marked as approved by us and placed on the timeline. If the mask had any issue, we would kick it back. That way we made sure we wouldn’t find the problem while we were in the middle of the color session and with little time to react.
To sum it up!
If I had to condense all the recommendations to work in a show like StartUp in just a few points, these would be:
Start work as early as possible.
Test everything as thoroughly as possible.
Talk with the deliverables department as early as possible to design the right workflow.
Work from bigger format to smaller.
Make sure you keep all the information and latitude throughout every part of the process, from acquisition to delivery, to avoid pinning yourself in a corner or losing quality.
Set the look of the show as early as possible so other decisions can be built on top of it.
Work intimately with other departments to reach the common goal of an amazing-looking show!