Modify image colours in ColorSync Utility on Mac
You can use ColorSync Utility to modify an image file by adding effects, changing the colour space, resampling the image or correcting the colours and brightness.
Choose a profile and intent
Go to the ColorSync Utility app
on your Mac.Choose File > Open, then select an image file.
When the file opens, click the first pop-up menu in the bottom left of the window, then choose an option.
Match to Profile: Changes the colours in an image to match the ColorSync profile. ColorSync Utility modifies the pixels in the image to match the new colour model and ColorSync profile, then assigns the new ColorSync profile to it.
Assign Profile: Assigns the ColorSync profile for an image. ColorSync Utility doesn’t modify the image saved in the file; it changes only the ColorSync profile for the image.
Apply Profile: Modifies the pixels in an image to match the new colour model and ColorSync profile, then assigns the image’s original ColorSync profile to it.
Click the second pop-up menu in the bottom left of the window, then choose a profile.
Click the pop-up menu in the bottom right of the window, then choose the intent of the colour profile, such as perceptual, colorimetric or saturation. See Set colour printing options.
Click Apply to save the changes to the file.
Adjust the colours and exposures in an image
If an image is too bright or dark, doesn’t have enough contrast or needs to be sharper, you can improve it.
Click 
in the image’s toolbar.
Apply tone mapping to an OpenEXR image
You can adjust the knee high, knee low, defog and exposure of a high dynamic range (HDR) image to the narrower range of a standard dynamic range (SDR) image.
Click 
in the image’s toolbar.