As suggested in the feature requests for 0.5<http://groups.google.com/group/scikits-image/msg/ddda01a609f41fd5>, I just added an exposure module<https://github.com/scikits-image/scikits-image/pull/103>with histogram equalization based on code by Jan Erik Solem<http://www.janeriksolem.net/2009/06/histogram-equalization-with-python-and.html>(with the author's permission). Anyway, please look over the pull request. It's probably a lot more complicated than it needs to (especially given the terse code that it was derived from). I took some pains to return an image of the same type as the input, and I added a histogram function which tries to figure out the correct binning for image intensities (there's probably an established way of doing this that I'm missing). Enjoy! Cheers! -Tony