Charles Tilford (a.k.a. listentoreason) sent me a tip about another photograph editor called LightZone for Linux. I haven't had much time to experiment with it, but it looks to be a pretty sweet little package. This is $250 software on Windows or Macintosh but free for
nerds linux users. Score! Here's a quote from their homepage:
Drawing on principles behind the photographic Zone System and traditional darkroom film photography, LightZone 2.1 makes it simple and easy to bring out the true tone, color and contrast often hidden in digital images. Designed by photographers for photographers, LightZone 2.1 offers a rich set of powerful, yet easy to use digital editing tools. LightZone's editing tools help reduce the noise often found in high-ISO digital images, correct color shifts and white balance errors, selectively sharpen or blur images or parts of images, remove dust spots and boost overall color to create beautiful, breath-taking images, letting the true talent of the photographer shine though.
Note: it's not open source, but it is free. Take that for what you will. I'll be checking it out sometime this week depending on my free time.