Tutorial: straightening a panorama

A common problem when creating a panorama is a curved horizon. See the following example:

This can occur if the panorama was taken with the camera pointing upwards or downwards, or if an anchor image was rotated during optimization. Because the panorama is a projection of a sphere (the world around the camera) onto a flat surface, tilting a panorama results in this snake-like curve.

PTGui has a 'straighten panorama' function, which straightens the panorama by just one click on this button:
In most cases, this will work fine. If it fails, or somehow gives unexpected results, here's how to straighten a panorama manually:

When straightening a panorama, the goal is to have the horizon of the scene exactly in the middle of the panorama. This means that it should match the horizontal line in the panorama editor. To achieve this:

  1. Open the Panorama Editor
  2. Switch to Panorama Edit mode:
  3. Use the left mouse button to drag a point on the horizon into the center of the panorama editor (where the two lines cross)
  4. Use the right mouse button to drag another point on the horizon to the horizontal line in the editor. On a Mac with a one button mouse: hold down the Ctrl key while dragging the panorama.

Now the horizon of the scene should match the horizontal line in the panorama editor.

The following animation shows the steps:

PTGui and PTGui Pro are products of New House Internet Services B.V., Rotterdam, The Netherlands. The PTGui and PTGui Pro software, related documentation and all contents on this site are © Copyright 2000-2024 New House Internet Services B.V., Rotterdam, The Netherlands. All rights reserved.