Adjust image brightness, contrast, and colour balance

When adding an image to an object file, in the Image import window:

1. If the checkbox labelled Make no changes to the image is checked, click it to enable the image processing tools. *
2. The Exposure settings let you adjust the brightness and contrast of the image.
3. The Colour balance settings let you adjust the amount of red, green and blue in the image (or cyan, magenta and yellow if you prefer to think of colours subtractively). Changing the colour balance can also affect the brightness of the image and you may need to manually compensate for this using the Exposure settings.

* Images in object files are always stored with JPEG compression. When adding an image file which is already in a JPEG format, the default behaviour is to keep the image data intact, preserving the image quality. If any changes are made to the image then it has to be recompressed. Unchecking the Make no changes to the image checkbox enables recompression as per the JPEG quality setting, and enables all the image processing tools. PNG and TIFF files are always recompressed.