Apple Color 1.5 - Manual (Page 254)

• Kelvin: This value is set by options in the RED camera’s Color Temp menu, along with
Tint. This setting is designed to compensate for the “warmth” of the available lighting
to keep white elements of the scene looking neutral. Low Kelvin values will compensate
for “warmer” lighting (such as tungsten), while higher Kelvin values compensate for
“cool” lighting (such as noon-day sun or overcast days). Two user-selectable options
set Kelvin to predetermined values: Tungsten (3,200K), and Daylight (5,600K). The Auto
WB option automatically chooses a custom value for this parameter based on analysis
of a white card, while Manual WB lets the operator choose any value. The correction
made by this parameter is designed to work specifically with RED linear light image
data to provide the most photometrically correct result.
• Tint: This value is adjustable within the RED camera’s Color Temp menu, along with
Kelvin. Tint is designed as an additional white balance compensation for light sources
with a green or magenta component, such as fluorescent or sodium vapor bulbs. The
correction made by this parameter is designed to work specifically with RED linear light
image data to provide the most photometrically correct result.
• Exposure: Available in the RED camera’s Color menu. Increases and lowers image
lightness in increments calibrated to ƒ-stops. When raising the signal up to 100 or
lowering it down to 0, the image is clipped at the boundaries of broadcast legality. The
overall range is –7 to +7, where 0 is unity.
• Red, Green, and Blue Gain: Available in the RED camera’s Gain submenu. Allows individual
adjustment of each color channel. Adjusting any of these gain parameters boosts or
lowers the maximum value of the corresponding color channel and scales the midtones
while pinning the bottom of the channel to 0 percent. Lowering does the opposite.
The overall range is 0 to 10, where 1 is unity.
• Contrast: Available in the RED camera’s Color menu. Raising the contrast boosts the
highlights and lowers the shadows, while leaving the midtones centered around 50
percent unaffected. As the video signal reaches the boundaries of 100 and 0 percent,
it’s compressed rather than clipped. The overall range is –1 to +1, where 0 is unity.
• Brightness: Available in the RED camera’s Color menu. Raises and lowers image lightness.
When raising the signal close to 100 or lowering it down to 0, the image is compressed
rather than clipped. The overall range is –10 to +10, where 0 is unity.
• Gamma pop-up menu: In-camera, the Gamma setting is determined by the Color Space
option that’s selected in the RED Camera’s View menu. (It’s not available as an
individually adjustable parameter.) There are six options for gamma available in Color.
• Linear: No gamma adjustment is applied, linear-to-light as captured by the Mysterium
sensor.
• Rec. 709: The standard Gamma curve as specified by the Rec. 709 standard for video
gamma.
• REDspace: Similar to Rec. 709, but tweaked to be perceptually more appealing, with
higher contrast and lighter midtones.
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