Sigma 8mm Fisheye Canon 350D MrotatorCP

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  • Sigma 8mm f/4
  • Canon 350D
  • Agnos MrotatorCP


  • With the above combination I can shoot a panorama in either six or three shots with yaws of 60 or 120 degrees respectively.
  • For the three shots process, position the camera 4mm backward in relation to its calibrated position for the six shots process.
  • If your aim is the three shots process (a time winner for cheap real-estate service), you will be better served with a Nikon D70 for which the MrotatorC was originally designed. It has a larger sensor, which gives you more overlap. The overlap of the images with the Canon 350D is extremely small.


The process that works for me (with PTgui):

  • import source images
  • set approximate lens settings
  • set panorama settings
  • the crop is automatically good
  • set image parameters
    • distribute images by yaw (thank you Joost for the Fill yaw function!)
    • roll all images -60 (the Agnos MrotatorC holds the camera at 60 degrees to use as much possible of the sensor surface)
    • set approximate pitch (thank you Luca for the great idea of orienting the camera slightly up, giving better coverage of the zenith)
  • set control points (i add at least two vertical lines)
  • first advanced optimizer run:
    • pitch on all images, including anchor image, linked
    • all lens parameter excluding horizontal shear (g)
    • important: no optimization of yaw and roll. The MrotatorC is solid and precise. I shoot with a wired remote and found that the positions are very consistent
  • second advanced optimizer run: if necessary, optimize a second time for all parameters including yaw and roll
  • blend and stitch, serve hot with either a Java applet or QuickTime

Lens Parameters

Can be stored in PTgui's lens database

  • lens type: circular
  • HFOV 165.482
  • a: -0.023487
  • b: 0.022401
  • c: -0.047265
  • d: 11.088037
  • e: 36.365823
  • g: 0
  • t: 2.753861


  • the above process works with my guinea pig, a little 5x5 (1.50mx1.50m) shower/wc room, as well as with some larger rooms.
  • I did not have to run the second optimizing run
  • Hypothesis: since the entry point of the lens changes with the angle, for a perfect, uncorrected stitch exact slices should be used, like an orange. To be verified.


Michel Thoby has studied the Sigma 8mm in detail Agnos MrotatorC