Doug Kerr
Well-known member
For a while, in an effort to be "scientifically rigorous", I have used the terms yaw, pitch and roll to refer to the three rotation movements of a typical tripod head and to the axes about which those movements take place. (Most commonly, in photographic practice, these are called "pan", "tilt", and something else - maybe "horizon level", maybe "landscape/portrait".)
Recently, I reported that I had a change of heart in that regard. Formally, the yaw, pitch, and roll axes are defined in a frame of reference locked to the object whose rotation is being described (in our case, the camera), and thus did not properly apply to axes defined in another frame of reference (such as the ground, or the tripod itself). Thus the axis we often call "tilt", because it does not have a fixed orientation with respect to the camera is not properly called the pitch axis, nor is the axis we often call "pan" properly called the yaw axis.
Thus, I reported, I would henceforth call the movements of the typical tripod head (and the associated axes) azimuth, elevation, and roll.
Further study shows that the situation is not that simple, and I now have a new outlook.
******
I won't torture you here with a detailed technical discussion. The bottom line, though, is this:
• The three angles we set with the three movements of a typical tripod head can be properly called the yaw angle, pitch angle, and roll angle, which describe the "angular attitude" of the camera.
• However, the axes about which change in yaw angle and pitch angle occur are not properly described as the yaw and pitch axes of "the system". [Yes, that sounds curious, but see the indented paragraph above.]
With all that in mind, I now have no problem in our speaking of the three movements of the typical camera tripod as the yaw, pitch, and roll movements.
And I think that, so long as we are clearly speaking of the tripod head itself, to describe the axes of these movements as the yaw, pitch, and roll axes of the head is a reasonable, and practical, departure from technical rigor.
Those who would like to look into the theory of all this may wish to consult the useful Wikipedia article, here:
http://en.wikipedia.org/wiki/Yaw,_pitch_and_roll#Aircraft_attitude
Recently, I reported that I had a change of heart in that regard. Formally, the yaw, pitch, and roll axes are defined in a frame of reference locked to the object whose rotation is being described (in our case, the camera), and thus did not properly apply to axes defined in another frame of reference (such as the ground, or the tripod itself). Thus the axis we often call "tilt", because it does not have a fixed orientation with respect to the camera is not properly called the pitch axis, nor is the axis we often call "pan" properly called the yaw axis.
Rigorously, the pitch axis always runs from one side of the camera to the other, parallel to its "baseplate"; the the yaw axis always runs from the bottom of the camera to its top; the roll axis runs fore-and-aft, parallel to the normal optical axis of the camera. Only the roll axis is a movement axis of a conventional camera tripod head (and then only if we mount the camera as "suggested" by the manufacturer).
Thus, I reported, I would henceforth call the movements of the typical tripod head (and the associated axes) azimuth, elevation, and roll.
Further study shows that the situation is not that simple, and I now have a new outlook.
******
I won't torture you here with a detailed technical discussion. The bottom line, though, is this:
• The three angles we set with the three movements of a typical tripod head can be properly called the yaw angle, pitch angle, and roll angle, which describe the "angular attitude" of the camera.
• However, the axes about which change in yaw angle and pitch angle occur are not properly described as the yaw and pitch axes of "the system". [Yes, that sounds curious, but see the indented paragraph above.]
With all that in mind, I now have no problem in our speaking of the three movements of the typical camera tripod as the yaw, pitch, and roll movements.
And I think that, so long as we are clearly speaking of the tripod head itself, to describe the axes of these movements as the yaw, pitch, and roll axes of the head is a reasonable, and practical, departure from technical rigor.
Those who would like to look into the theory of all this may wish to consult the useful Wikipedia article, here:
http://en.wikipedia.org/wiki/Yaw,_pitch_and_roll#Aircraft_attitude