Here is what happens
1- Some Red footage has been pre-graded on set with RCX. They used a bunch of custom looks saved as a RMD files.
2- I AMA the Red files in the editor and the custom looks are effectively applied automatically so I can see the clips colored as the dp's did in RCX, I can see the custom names, the color spaces (red color 1 2 and 3), the gamma etc etc...
3- Instead of cutting directly the R3D, I choose to use a DNxHD 36 workflow as it's big volume, and make my edit. All fine.
4- Plans have been changed. Originally, the footage would have been sent to Nucoda but the prod decided that it has to be finally graded and finish in HD within the editor for costs reasons and also, that the custom presets used on set aren't valid anymore and a completly different look has to be applied, but they didn't send any alternative RMDs. In short, we restart from zero in what color is concerned and have to color-finish in Avid. Fine, yeah...no roundtripping.
5- I conform within the editor relinking the DNxHD edit to the source material
6- My plan consists now in desapply the R3D looks done in RCX on set without using RCX to recover the flat images and therefore starting with the max DR to color correct in the editor in RGB mode. I do this cancel from the editor.
And this is where I have the question:
What I do is this: to revert to the flat file, basically I say to Avid: "no, this look isn't suitable anymore. I want you to apply
-Color Space: REDspace or camera RGB
-and for Gamma Curve I choose: REDlog film.
Avid obeys like a little dog. It works fine. All the timeline is now as flat as Jane Birkin's breast.
The only problem is that it works but I don't do that from real knowledge but from logic-intuition.
I could for example revert to camera metadatas settings, but it doesn't give me flat files to work with but a Scurved look. I don't really get this "camera metadatas settings" option and why it's not flat. Why don't they shoot flat in-camera? if everything will be color corrected? Are there really people who shoot documentary-news with RED cameras?
In terms of color space and gamma curves, the options availables in the editor are those:
Color Space: RedColor 1, 2 and 3 / Rec 709 (no because I will CC in RGB) /sRGB / Adobe 1998 /Redspace/camera RGB
I really do not get what are those Redcolor 1,2,3. Yes it changes but slightly, for example the differences between RedColor 2 and 3 are subtle, perfectly visible in curves.
And what the hell is this REDspace? Camera RGB is the less saturated.
I do not master this Red science enough to really understand what is involved behind the scene. The thing I'm doing is to choose the flatest possible look for grading trusting my eyes and the curves just by tricking options.
Then, in terms of Gamma curve, here it is more simple because to revert to flat I obviously have to Log them but...there are 2 options:
The flattest to my eyes being REDlog film so I simply choose REDlog film, but again, I choose it because of the result I see, not because I know about it. Why co-exist those 2 REDlog flavors? Why not just REDlog film to have the widest DR?
What I'm seeing in Avid is that REDlog film is driving more towards the shadows while REDlog towards the Highlights, but that with REDlog film the work on the HL is easier because they clip later.
In fact, maybe REDlog film isn't flatter as REDlog, it just seems to be distribuited diferently and looks flatter but isn't.(?)
The same with REDcolors, why 3 flavors? and what is the guide to choose the right one?
If some Red users could share their experiences on that it would be great.