How to resize 4K R3D to 2K R3D?

[SandeepDey]

I am working on a new workflow, in which I would like to shoot 4K (for obvious reasons) but post in 2K to keep a fairly uncomplicated FCP process.

So the question is, how can I resize 4K R3D footage to 2K R3D footage?

The objective to keep the 2K in R3D is so that we retain the best quality imagery until we are ready to commit to the grading.

 

[David Mullen ASC]

You can't. I mean, you could try, but it's not going to help, quality-wise, compared to converting 4K R3D to RGB and then resizing to 2K RGB. You aren't losing quality by converting to RGB unless you do it badly.

RAW means it's a monochrome image with a mosiac filter pattern in the original photography, making it very hard to downsample RAW to RAW, and doing that can lead to all sorts of odd artifacts -- you're much better off converting to RGB and then downrezzing to 2K RGB.

Storing the image as 2K RAW means that you'll get a worse 2K image than downrezzing from 4K RGB to 2K RGB. Because you'll have to generate RGB from a bayered 2K image, which ends up less than 2K in terms of measurable resolution because the bayer pattern in 2K RAW has 1K worth of green photosite information and .5K worth of red and blue individually from which to build an RGB image.

Storing as "RAW" only ensures the best quality if it truly is RAW -- what the sensor captured. Downsampling it RAW to a smaller RAW file does not mean you're getting more quality compared to converting it to RGB and then downsampling that -- in fact, it's worse as I pointed out because you're ending up with less information from which to generate 2K RGB.

 

[Ted Chu]

Post in 2K

Post in 2K

Do you mean post in 2K MOV and not R3D? If so, try this common workflow:

1. Double backup.
2. One light color correct on RedAlert creating a RSX file.
3. Render in 2K with RedRushes or Clipfinder using the RSX file as your LUT.

Alternatively, you can color correct with RedAlert, save a Preset, and import directly into FCP using Log and Transfer choosing that Preset under preferences.

 

[Uli Plank]

But in the latter case a few parameters like curves are not observed (see whitepaper).

 

[jimhare]

Another option is to just use proxies or reference pro-res for editing, then return to your R3Ds for grading.

This would happen automatically in Color (it uses your 4k R3D at 2k) or fine in Scratch (uses your 4k at 4k) or use Crimson to bring it back into RedCine.

As David says, there is no way to create a new R3D, and you really wouldn't want to anyway.

 

[SandeepDey]

Thanks for all your responses, gents.
-s