I don’t get a whole lot of RED footage but it occasionally comes in for color. Any RED experts here that can explain OLPF and what settings you typically use? Or is it just a matter of looking at the footage and deciding if it needs the sharpening?
I’ve only had it matter a handful of times. If they shot with an optical lowpass filter and you turn on that setting you will see the footage get sharper. I haven’t seen one used in years, though. In my experience if they didn’t use one, toggling the setting on doesn’t visually do anything so I just leave it on all the time rather than having to constantly test.
The OLPF is actually a hardware filter on the camera, which exists on almost every camera with a bayer sensor. But on RED cameras you can switch between different versions, which can affect the picture. But those changes are baked, nothing you can do about it in post.
There is a setting apparently that compensates for different OLPF sharpening. Here’s a some useful guidance on it: R3D Sharpening | Lift Gamma Gain - Colorist & Color Grading Forum
The OLPF filter choice is different than the RED parameters you can adjust in the RAW settings of the RED clip, like highlight roll-off, etc. There are a whole number of parameters you can adjust. In most cases that shouldn’t be necessary, but in a difficult shot it can make the difference between good and great results.
That’s the one reason to avoid using ProRes files from a DIT on RED cameras, because then these settings are also baked. If it’s a good DP + DIT, all good. But I’ve seen both sides of it.
Here’s a link with some info on the OLPF: https://www.red.com/red-tech/Optical-Low-Pass-Filters-OLPFs
One thing that is worth looking at - RED shooters sometimes have a bad habit of not setting the ISO or the white balance on the camera correctly, because they know it can be changed in post. Close enough is good enough for some of them.
The end result can be an under-exposed shot. And then if you go in and pump up the gain in a color correction node to bring this shot into the proper range you can end up with a noisy mess because you’re doing competing corrections. In those cases it’s better to go into the RAW parameters and change the ISO and color temp sliders so it interprets the sensor data properly and you end up with a cleaner overall picture.
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