T3i Locking Exposure in video mode?

[Cammmer]

When some one moves an arm on camera I can see the exposure changing on the lcd monitor. Using older lenses I can see exposure changing/flickering as I zoom in or out.

How do you lock exposure in video mode?  Even my several year old HV20 had a not-in-the-manual way of locking exposure.

Any video people here? I know how you lock exposure for still photography. I'd think the answer to this would be out there and not something that even stumped my local camera store.

[jrhoffman75]

http://www.dvinfo.net/forum/canon-eos-crop-sensor-hd/498717-manual-exposure-settings-video-mode.html

[Cammmer]

Thanks, I will have to reread your link and experiment with my camera tomorrow. The only thing it seems right now that I was doing wrong was leaving the ISO to AUTO. Also, I am using older lenses which flicker exposure when zooming(possibly in Auto  ISO). One newer lense doesn't seem to flicker exposure changes when zooming even in Auto ISO.

MAYBE the non-zoomed, tripod shops where the exposure changed with the moving of the actors arm I took a few days ago was soley related to ISO on AUTO.   I HOPE. Otherwise, I don't see a solution to a such a seemingly simple problem.