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Notes on colour measurements


All color readings are taken with a layer of Lee 216 between light and meter. Lee 216 has a slight warming effect, so measured CCTs in this test will be lower than CCTs from direct measurements of the lights.

When a light was dimmed, its dimming is shown as a percentage, for example @ 86%. The Rotolight Titan was dimmed using its built-in diffusion panel, and its diffusion setting is shown instead.

The ETC fos/4 offers “Brightest” mode which maximizes output at the expense of spectral quality, “Spectral” mode which sacrifices output but provides the best color quality, and “Hybrid” mode that splits the difference. We used “Spectral” mode for the camera tests but I also captured C-800 data in “Brightest” mode for comparison. “Spectral” is shown as “Spectrum” in the charts.

Color data shown for the Kino Flo Diva-Lite 21 was captured with its “camera LUT” setting at “KF Default”.

For tint, “+G” readings are equal to 100 * ∆uv (a.k.a. Duv). 1 +G ≈ Wratten CC30G.

The horizontal divisions on the tint chart are in 1/8 +G steps. Most gaffers I speak with consider ± 1/8 +G the smallest noticeable tint change, and most won’t even correct for less than ± 1/4 +G (two divisions on the tint chart).

The horizontal divisions on the 3200 K CCT chart are in 100 K steps. The horizontal divisions on the 5600 K CCT chart are in 500 K steps. These divisions are roughly comparable in terms of perceptual difference in CCTs at those two different color temperatures. 

Lumu Power version 1 readings sometimes exceed the ranges shown on the charts. Lumu Power version 1 is obsolete but its readings are shown for completeness, as many of these devices are still in use. Lumu offers an upgrade program from version 1 to version 2.

Lumu Power tint readings do not appear to be usable in the current software. Lumu has been informed, and they say they’re working on improving tint readings in a future software release.

Lumu Light Meter app version 3.3.3 was used in this test. 

Cine Meter II beta version 4.0 was used in this test; its color metering is unchanged from the current shipping version, 1.21. Prior to testing, both Cine Meter II iPhones were color-calibrated to match the C-800’s readings under unfiltered tungsten light from the DeSisti 5k.

Our cinematographer Marina occasionally used her Sekonic C-700 to check the light. Whenever she mentioned a reading, it was always within 100 K of the C-800 reading and usually within 50 K.



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