I have written a basic tutorial for straightening panoramas by using
vertical control points.
English:
http://www.dffe.at/pano360/pano-horizont-360_en.html
German:
http://www.dffe.at/pano360/pano-horizont-360_de.html
Feedback and suggestions are very welcome!
Best regards
Bernhard
--
Bernhard Vogl
Vienna, Austria
http://dativ.at
http://www.austria-360.at
Tutorials: http://www.dffe.at