Canon 600d crop factor -> lens?

[chazfest]

Hey guys,
I'm shooting a ton of test plates right now to practice tracking/matchmoving and comping to. I'm shooting them on a 600d and wondered if anyone can enlighten me as to how/if the crop factor (1.6?) affects the focal length of the lens?

For example, when I'm setting up the CameraTracker in Nuke, or editing the prefs in PFTrack, I've been putting the focal length of my Canon 50mm lens down as exactly that, 50mm. But am I right in assuming that I should be taking into account the crop factor of my camera in order to get the correct focal length?

If so, would I simply divide the focal length by 1.6? Giving my 50mm lens a focal length of 31.25mm?

Any tips or advice would be amazing.
Huge thanks in advance.

[pingking]

the focal length printed on the lens is mostly messured for a full format sensor, so you have to MULTIPLY it with your crop factor. http://en.wikipedia.org/wiki/Crop_factor

most of the times its better to give the tracker the right size of the sensor and lets guess them the focal length/fov settings. it also helps you to judge the quality of the track. if the computer say its near the lens you used, then the track is on a good way