AND WHY YOU SHOULD NOT USE THEM
What is a LUT?
A LUT, a lookup table, transforms tone and color based upon settings chosen by the creator of the LUT. A LUT transforms incoming RGB data to your desired output values. Originally, LUTs were designed for practical purposes. A “Viewing LUT” would allow you to make log footage look like rec709 footage, so you had a better representation of what your final film would look like. “Calibrations LUTs” are used to calibrate monitor displays. There are “film emulation LUTs” that mimic the look of stock film. More recently, LUTs have been employed for creative purposes. (Creative LUTs).
In order for a LUT to be 100% precise the input has to match the conditions in which the LUT was created, likewise the output has to match 100% as well. You have to know exactly what your input device and output device will be. This is why LUTs are mainly used in-house at post-production houses or colorists working on their own stations.
How to find out if a LUT is bad?
It can be difficult to objectively judge the quality of a LUT being provided when applied to real-life footage. For me personally, I think the easiest way to analyze a LUT is using a Test Chart.
So here are some “BAD LUTs”. It should be clear that you might run into banding and artifacts issues with those LUTs.
These tested LUTs come from very popular and expensive LUT packages. The people behind it describe themselves as “Leading Developer”, “Industry standard” and write sentences like “Trusted by professionals” on their websites. They name clients like: Netflix, Sony, Universal, Nike, Adidas, on their pages. But none of these LUTs I’ve tested so far are “professional”. Quite the opposite.
SUMMARY & ADDITIONAL VIDEO
Let’s summarize the most important points:
- Use trustworthy LUTs only.
- LUTs can be a very helpful tool by achieving a certain Look which are not achievable with tools inside DaVinci Resolve. Just test those LUTs using Test Charts and make sure that they will not “break” your image.
- Using a “Clean LUT” can be a great starting point.
In my latest “Soft 2 Strip” Project you can see the strength of a Power Grade which I build around a Kodak 2383 LUT. This is a good example of how PowerGrades and a clean LUT works perfectly well together.
Also check out my video I made on this topic:
WORKING WITH LUTS
TRILINEAR / TETRAHEDRAL
There are two ways LUTs are interpolated in DaVinci Resolve. By default, it is set to “Trilinear”. It is better to switch to “Tetrahedral”. It takes a bit more processing power but it will give you much better, cleaner results.