An Introduction to RawTherapee and Darktable

Neil Schemenauer

Presentation Outline

  • Why use RAW and extra processing software?
  • Why consider open-source software?
  • Introduction to Darktable
  • Introduction to RawTherapee

Why not use RAW?

  • Larger file sizes (e.g. 4X)
  • More time to process, more steps
  • Don't have processing sofware
  • Don't know how to use processing sofware

Why use RAW?

  • More information, higher image quality
  • Artistic control

More information in RAW files

  • More dynamic range (levels pure black to pure white)
    • High end camera has near 14 stops.
    • JPEG can only encode 8-bits per pixel
  • More resolution
    • No demosaic (detail vs artifacts)
    • No noise reduction (detail vs noise)
    • No sharpening (do it last)

Artistic control

  • Exposure
  • White balance
  • Tone map (selective exposure adjust)
  • Amount of noise reduction, sharpening
  • Choices are interactive (undo, large screen)

Dynamic range and tone mapping example

Ansel Adams: Moonrise, Hernandez, New Mexico

Why open-source software

  • Lower cost (e.g. Lightroom $10/month)
  • More control (upgrades, multiple computers)
  • Different set of features
  • Try something different

Non-destructive photo editing

  • RAW files remains untouched
  • Redo processing without loss of quality
  • Easily have multiple developments
  • Side-car files, easy backup

Operating Systems Supported

LinuxYes (primary)Yes
Mac OSYesYes
WindowsNo (beta)Yes (primary?)

Darktable, file import

Darktable, interface layout

Darktable, white balance

Darktable, zone system

Darktable, zone system 2

Darktable, expand low-lights

Darktable, expand high-lights

Darktable, duplicate

Duplicates processing history stack, not RAW image.

Darktable, B&W

Darktable, export to JPEG

Darktable, final image

Out of camera JPEG

RawTherapee, file browser

RawTherapee, high ISO noise

RawTherapee, after NR

RawTherapee, reduce exposure

Reduce exposure by 1/2 stop, recover detail in sky.

RawTherapee, queue for processing

RawTherapee, final image


  • Internet search
  • YouTube
  • Harry Durgin:, parametric masks