Image Adjustment

Displays a graphical representation of the tonal values in the image.

• Black point: The point at which solid black occurs (black triangle).
• Gamma: Controls the overall brightness of an image.
• White point: The point at which solid white occurs (white triangle).

All channels are initially displayed.

If Ungroup Color Channels is checked, each channel is listed and may be modified.

To hide a channel, clear the check box next to it.

Apply changes to stack: Changes are applied to each image in the image stack.

You have the option to display Gain and Offset instead of Brightness and Contrast:

• Click Show Options.
• Under Display Options, next to Work with, select Gain / Offset controls.

Reset: Resets the image to its original settings up to the last save.

Default: Sets the Black Point to 0 and the White Point to the highest value available for the image's bit rate.

• For an 8-bit image, the highest White Point value is 255.
• For a 12-bit image, the highest White Point value is 4095.

Optimize: Sets the Black Point to 0 and the White Point to the brightest value available for a pixel. You can apply this command to one or more selected channels at a time.

Show/Hide Options

Show Luminance: Only available if the channels are grouped.

Use Simple Color Pickers when selecting colors: Determines which color the program displays.

Optimization Options: The More button allows you to adjust the optimization settings.

Channel mixing:

Add

Adds the values of the selected channels. The resulting value is never higher than the highest value available, 255 for 8-bit images, 4095 for 12-bit images, etc.

Example for an 8-bit image: 

• Red channel: 100 / green channel: 20 / blue channel: 200
• The total value is 255 because 255 is the maximum value and 255<100+20+200.

Max

Uses the maximum value of the channels.

Example for an 8-bit image:

• Red channel: 60 / green channel: 230 / blue channel: 225
• The resulting value is 230 because 230 is the maximum value out of the three channels.

Average

Displays the average value of all channels.