December 30, 2025

Rotate and Perspective – For straight horizons and perfect architecture

What is it about?

Nothing ruins a good landscape or architectural photo faster than a crooked horizon or converging lines (when buildings seem to “topple” backwards). The “Rotate and Perspective” module is your tool for the geometric correction of the image.

The most important functions:

  • Rotation: Corrects a crooked horizon.
  • Keystone Correction: Aligns vertical and horizontal lines so that buildings stand straight.
  • Automatic Cropping: Automatically adjusts the image after rotation so that no black edges appear.

How to apply it:

The easiest way is the automatic structure detection.

  1. Open the module.
  2. Click on the icon for “Automatically detect structure” (4 vertical lines).
  3. Darktable analyzes the image for straight lines and aligns it automatically.
  4. You can manually readjust using the “Rotation” slider.

Pro Tip: Quick alignment via mouse

You often don’t even have to open the module to rotate the image: simply hold down the right mouse button in the darkroom and draw a line along the horizon. As soon as you release, darktable rotates the image straight.

Genius: This works just as well for vertical lines! Simply draw the line along the edge of a building or a pole, and darktable aligns the image to it.

For more information, view darktable’s official manual page: “rotate and perspective”
Questions about this topic? Discuss it with us in the forum!

Leave a Reply