Most Raw photo editors require users to pay a recurring subscription fee or purchase a user license, sometimes costing hundreds of dollars. RawTherapee is a free alternative that allows photographers on Linux, macOS and Windows to develop Raw files from a wide range of cameras. The open-source RawTherapee has now been updated to version 5.9. The major update comes over two years after version 5.8 was released.

Highlighting the new release is a long list of new features and improved camera support. Starting with the features in the app's Details tab, the team has added a Spot Removal tool for removing dust specks and small objects from your images, plus a new saturation slider to the existing Haze Removal tool.

Within the Color tab, there's a new automatic white balance method called 'temperature correlation.' The old auto white balance tool remains under a new name ('RGB grey'). The Film Negative tool has been improved, including with support for non-Raw images.

The app's Raw tab includes a few improvements, including a new Pre-process White Balance tool. This tool allows the user to specify whether channels should be balanced automatically by the app, or if the values recorded by the camera at the time of capture should be used instead. There are new dual-demosaicing methods in the Demosaicing tool, plus a Pixel Shift demosaicing method that allows for an average of all frames to address motion across multiple frames. Concerning Raw image editing, the app uses a non-destructive 32-bit (floating point) processing engine alongside modern demosaicing algorithms. It can also edit high dynamic range DNG files. The app also supports pixel-shift compositing with automatic ghost masking, multiple-frame Raw files, dark frame subtraction, flat field correction and hot/dead pixel correction.

RawTherapee 5.9 includes non-destructive 32-bit Raw image editing with advanced demosaicing algorithms and many Raw image editing tools

For in-depth photo editing, the app includes an Advanced tab. While many adjustments are easy to understand for beginners, the app includes features for more advanced users, including a Color Appearance & Lighting tool, formerly known as CIECAMO2, that includes CAM16. This option allows the user to adjust colors in an image more in line with typical human perception. The Wavelet Levels tool has undergone improvements.

RawTherapee 5.9 adds better support for local adjustments. The Local Adjustments tool was added to the Local tab, allowing the user to perform many different operations within a specific area of the image, as determined by geometry or color.

RawTherapee 5.9 includes improved local adjustment tools

Additional improvements include a new Perspective Correction tool (Transform tab) that allows for automatic perspective correction, an improved UI theme that makes it easier to see which tools are in use, the option to resize an image by its long edge or short edge, and a 'centered square' crop guide designed for working on images intended for use on social media.

Many cameras have received new or improved support for Raw formats and color profiles, including many cameras from Canon, Fujifilm, Hasselblad, Leica, Nikon, Olympus, Pentax, Panasonic, Ricoh, Sigma and Sony. Click here for the full list of cameras with new or updated support.

RawTherapee 5.9 is available now for Linux and Windows. You can download the latest version and the source code here. The macOS version is not available yet. Using any photo editor can come with a bit of a learning curve, but RawTherapee provides an in-depth user guide to help photographers of every skill level get the best from their Raw images.