LightZone

LightZone is a professional-level digital darkroom and photo

editor for Mac, Windows, and Linux. It includes RAW processing

and editing. Rather than using layers in the way that other

photo editors do, LightZone lets the user build up a stack of

tools which can be rearranged, readjusted, turned off and on,

and removed from the stack. It's a completely non-destructive

editor, where any of the tools can be re-adjusted or modified

later — even in a different editing session. A tool stack can

even be copied to a batch of photos at one time. LightZone

always operates in a 16-bit linear color space with the wide

gamut of ProPhoto RGB.