F35: Alexa lut for the F35?

Here you go:


Here's some Sony F35 footage recorded in S-log/S-gamut 6 years ago re-exported with a newly developed LUT.

The new workflow is as follows:
- my own S-gamut to rec709/sRGB color space conversion.
- levels adjusted to match Alexa log C curve.
- Alexa lut applied without any color space transformations (typically called 1D lut which should not affect colors - disclaimer, this is not the built in Alexa lut in davinci - which will affect/ruin colors - but a purposely one created through the arri lut generator)

This video has been exported as 4K in davinci to improve image quality and reduce compression artifacts inherit to youtube.

Shutter speed is very high due to not using ND filters on these tests.
 
macgregor said:
The new workflow is as follows:
- my own S-gamut to rec709/sRGB color space conversion.
- levels adjusted to match Alexa log C curve.
- Alexa lut applied without any color space transformations (typically called 1D lut which should not affect colors - disclaimer, this is not the built in Alexa lut in davinci - which will affect/ruin colors - but a purposely one created through the arri lut generator)
Click to expand...
What would be the point?

Perhaps I misunderstand, you adjust the Rec709 levels to match an Alexa log C curve and then apply a LUT to exactly undo that?
 
macgregor said:
Hi Cary, perhaps you got confused with colorspace and levels.
Click to expand...
You say you use your own LUT to do levels and color space conversion from Log to Rec709, then adjust the levels to match the levels of the Alexa log C curve and then apply a LUT without any color space transformation to go from Alexa log C levels to Rec709.

So I was asking what the point was in doing that as you seem to go from Rec709 to a log curve and then undo that same log curve by going again to Rec709 without any colos space conversions.

Where am I confused?
 
Last edited:
Cary Knoop said:
You say you use your own LUT to do levels and color space conversion from Log to Rec709, then adjust the levels to match the levels of the Alexa log C curve and then apply a LUT without any color space transformation to go from Alexa log C levels to Rec709.
Click to expand...



Nope, I dind't say levels, it's just colorspace.
 
Last edited:
macgregor said:
Nope, I dind't say levels.
Click to expand...
Oh I see, so you convert Log Sony Gamut to Log sRGB/709 Gamut, then you adjust the log levels to fit the Arri log levels and then convert Log to Rec709 (with no colorspace conversions).

Got it! (I still don't see the point of making adjustments to fit one log format to another one but at least I understand now what you are doing).
 
I clicked on the download and all i got was text. I messaged macgregor and he said to open with a PC but all i have is a MAC. Is this why i am having issues or am i doing something wrong?


This is what opens when i download it. And dropbox tells me it can't be previewed


TITLE "Generate by Resolve"
LUT_3D_SIZE 33

0 0 0
0.00317388 0 0
0.0193942 0 0
0.0385138 0 0
0.0620279 0 0
0.0918898 0 0
0.126909 0 0
0.168093 0 0
0.215717 0 0
0.267277 0 0
0.317357 0 0
 
Luts are just text like you posted. You might need to change the extension to the proper one. I believe this is a .cube file.
 
Been using this on a Mac without issue, just download/drop it in the right folder for your app.
 
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