The LUT that helps you keep subjects within 1.66 Stops Below (S-log3 27% IRE) and 1.66 Stops Above (S-Log3 55% IRE) Middle Gray whilst using S-Log3!
UPDATE: The V-Log Version is HERE
Goldilocks LUT is calculated to give you ‘just right‘ skin tones in gray scale exposure from minus 1.66 stops (27%IRE in S-Log3) to plus 1.66 stops (or 55% IRE in S-Log3) and anything outside of the ‘perfect’ sweet spots is coloured shades of gold as set out below. Personally, if I’m exposing flesh or most subject matters for correct luminance and color this is the area to have your limits in and so I’m not much interested in anything else!
Sony S-Log3 Stops/IRE Value Table for Goldilocks LUT
- Absolute black (0 to 3.5% IRE) Dark
- -8 stops (4 IRE)
- -7 stops (4.5 IRE)
- -6 stops (5.5 IRE) Darker Gold shades
- -5 stops (8 IRE)
- -4 stops (12 IRE)
- -3 stops (17.5 IRE)
- -2 stops (< 24.5 IRE) Dark Gold
- -1 & 2/3rds of a stop (appx 27 IRE) Darker Grey
- -1 stop (32.5 IRE) Dark Grey
- 0 stops (40.5 IRE) Middle Grey
- +1 stop (49.5 IRE) Light Grey
- +1.66 stop (55 IRE) Lighter Grey
- +2 stops (> 58 IRE) Gold
- +2.33appx stops (61 IRE AKA 90% White)
- +3 stops (67 IRE)
- +4 stops (76 IRE)
- +5 stops (85 IRE) Lighter Gold shades
- +6 stops (94 IRE)
- +7 stops (103 IRE)
- +8 stops (109 IRE) Clipping
Anything that ISN’T GOLD (Dark to Light gold) and coloured in grayscale is inside the sweet spot ie ‘just right’ as Goldilocks the story goes!
Goldilocks LUT placed over an Arri to S-Log3 transformed Color Chart
How to Use Goldilocks LUT
To use the LUT, place it over the top of any S-Log3 image, either in your camera, monitor or in an NLE (like on a secondary node in Davinci Resolve). Adjust your exposure in camera or in a BEFORE Serial node in Davinci Resolve using the Offset wheel until the image or subject sweet spot falls into gray scale and NOT gold shaded. Once you’re happy the exposure is gray scaled, switch off the LUT and replace or add another node with a rec709 normalised LUT (like Sony’s own S-Log to Rec709 LUT and you should have a perfectly exposed ‘just right’ image. Say bye to the three bears!
Download Link to the free 33 size Sony Version Goldilocks LUT: Goldilocks False Color for Sony S-Log3 by Nick Driftwood.cube
Here’s a few examples of how the LUT looks using the Panasonic Camera version:-
Shades of gold show under or over exposed areas e.g. – dark gold low reflectance, bright gold hi reflectance.
Enjoy using the LUT,
Nick Driftwood
