Allows you to adjust the range of brightness of the image.

Fast menu: 16átoá235

The default for video images.

Fast menu: 0átoá255

Allows you to map normal video to alpha ranges. This is useful if you have a high-contrast image that you want to expand to the full dynamic range. For example, use this value when you want to convert video to alpha for Matte Key effects.

W Point (whiteápoint)

Allows you to set the white point in the image. All pixels with that value become white, and all pixels with higher values are also clipped to white. The default is 235 (the broadcast value for white).

Raising the black point and lowering the white point values increase the contrast by reducing the number of shades of gray in an image. The number of shades is reduced because you map some to extreme black and others to extreme white.

B Point (blackápoint)

Allows you to set the black point in the image. All pixels with that value become black, and all pixels with lower values are also clipped to black.

For example, you could use the eyedropper to select a shadow on the floor and change it from gray to black, clipping everything below that shade to black. The default is 16 (the broadcast value for black).

Raising the black point and lowering the white point values increase the contrast by reducing the number of shades of gray in an image. The number of shades is reduced because you map some to extreme black and others to extreme white.

Gamma

Allows you to adjust the midtones in an image without affecting the extreme white or black values. Lowering the value darkens midtones and brings the image closer to black. Raising the value lightens the midtones and brings the image closer to white.

For example, a person shot in front of a window in daylight may be very dark, almost in silhouette. You can use gamma correction to increase the midtones without changing the blacks or whites. Values range from –100 to +100 with 0 being no change.

The W Point, B Point, and Luma Clip sliders determine the number of shades of gray. The Gamma point allows you to move the distribution of the shades closer to black or closer to white. Negative values move the distribution closer to black. Positive values move the distribution closer to white.