User guide

Viewing and Editing Images
12-29
Fig. 12-19. Images without and with Dark Contrast adjustment. Note that in Exam-
ple A, with no Dark Contrast adjustment (3.00 O.D.), the surrounding medium
appears free of background and image artifacts, but in Example B, with adjust-
ment (0.46 O.D.), artifacts in the image become immediately obvious, indicat-
ing that the subtraction levels were not sufficient to remove all background
artifacts from the gel image.
Background Slider
To manually adjust the background subtraction level for your image, drag the
Background slider to the right. You can also move the slider incrementally by
clicking on the slider bar, or you can type a specific background value into the
field next to the bar.
Objects with signal intensities lower than the subtraction level will be
eliminated from the image when you click on OK.
Background Box
This method of subtraction is best suited for images with uniform
backgrounds.
Example B: with adjustment
Example A: without adjustment