Calibrating a Panoramic Head for Your Lens By Dave Watts. To eliminate the possibility of parallax errors (things not lining up properly) when stitching individual frames into panoramics, it is necessary to calibrate your panoramic head for the lenses and focal lengths you frequently use. In this example we will calibrate a Really Right Stuff MPR-CLII nodal slide for a Canon 10-22 lens at 22mm in portrait orientation for use with the RRS L-bracket, and PCL-II panning clamp atop a BH-40 ballhead. The basics described here should apply no matter what equipment you use. I should mention this tutorial is meant as a guide for single-row panoramas.
An L-plate made for your camera model allows a convenient and accurate method of quickly locating the lens' center line whether you're mounting the camera in landscape or portrait orientation. Just line up the markings and tighten it up.
Both the slide and clamp have built-in levels (see last photo) to assure an accurately centered horizon line as you pan around.Notes: If you use zoom lenses, a lens' optical center (frequently and incorrectly referred to as the nodal point) changes for each focal setting. This means you'll need to calibrate for all frequently used settings. With my Canon 10-22, I have nodal slide settings for 10, 17, and 22mm. Oddly, the 10mm position is in between those for 17 and 22. A post-it tape chart is attached directly to the slide to look up often-used settings. These figures include the focal length, its nodal slide position, how many degrees to swing the upper rig for proper shot overlap and the number of shots I'll need for a full 360º pano if I decide that's what I want. Discuss this tutorial on Digital Grin Forums.