RawTherapee

Yes, RawTherapee is a completely free, open-source raw image processing software available for Windows, macOS, and Linux. It is built by a community of developers and relies on non-proprietary algorithms for image enhancement. Professionals often use it as a highly capable alternative to paid software like Adobe Lightroom.

RawTherapee is specifically focused on developing and enhancing RAW files from a vast array of digital cameras, utilizing the open-source dcraw code to interpret formats. The developers frequently update the software to support the latest proprietary RAW formats from manufacturers like Canon, Sony, and Nikon. If your camera shoots in a standard RAW format, RawTherapee can almost certainly process it.

RawTherapee offers highly advanced noise reduction tools that operate entirely on non-proprietary algorithms. It allows for both luminance and chrominance noise reduction, giving users micro-control over how much grain is removed from high-ISO images. Additionally, it provides detailed lens corrections and color correction sliders to salvage difficult shots.

Yes, like most dedicated RAW developers, RawTherapee operates entirely non-destructively. Instead of modifying the original RAW file, it saves all your color correction, noise reduction, and lens correction adjustments into a sidecar file (usually a .pp3 extension). You can always revert to the original image data at any time.