What is the order that LUTs are applied in RV?

RV provides four points in its color pipeline where LUTs can be applied: just after reading the file and before caching ( pre-cache LUT ) directly after the cache ( file LUT ), just before display transforms ( look LUT ), and as one of the display transforms ( display LUT ). The first three are per-source while there is only a single display LUT for each RV session. Display LUT typically contains only the physical monitor-specific transforms. You can see the full pipe here: Image Processing Graph

One thing to watch out for is that RV does have limitations on the values of what is acceptable in the LUTs. You can see the acceptable file formats and what min/max values those file formats can have here: LUT File Formats. If you have values in your LUTs that land outside of the range, you might get unpredictable behavior and clamping. Here are the permissible values:

Extension Type 1D 3D PreLUT Float Input Output
csp Rising Sun Research • • • • [ - ∞ , ∞] [ - ∞ , ∞]
rv3dlut RV 3D • • [0 , 1] [ - ∞ , ∞]
rvchlut RV Channel • • [0 , 1] [ - ∞ , ∞]
3dl Lustre • [0 , 1] [0 , 1]
cube IRIDAS • • [0 , 1] [ - ∞ , ∞]
any Shake • • [0 , 1] [ - ∞ , ∞]

Have you taken a look at the Custom LUT Menu Mode package? If you enable RV -> Preferences -> Packages -> Custom LUT Menu Mode and restart RV, you’ll get a Custom LUT menu (and the package itself has some great documentation on how to use it!). But what this will do is RV will look for a LUT in the same directory as your files (or specified directory, depending on your settings) and automatically apply these LUTs. This way you can stack your per-show and/or per-shot LUTs.

Here is a further breakdown of applying LUTs in RV.

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