Overexposure on Movie mode

[abrogard]

I live in the tropics. Bright sunlight. Sometimes I take a movie with my Powershot 520 outdoors and it is fine - exposure correct for the job. That's especially true, I think, when I'm in the shade of trees or somesuch all the time.

Othertimes the camera doesn't seem to adjust and overexposes the whole thing.

For instance I can commence a movie indoors and walk out into the shaded verandah - which has bright sunlight all around it, like 'walls' of sunlight, but is itself shaded (and has the house wall on the fourth side, too, providing another shaded direction.) and the movie will go into overexposure immediately, even though I am not directing the camera at the sunlight but am photographing things within the shade - ie. my son on his tricycle.

Another time I can do this and I do NOT get immediate overexposure.

1. Have a got a camera fault?
2. Is there something I can do to force the camera to adopt the right exposure?
3. Any other hints?

regards,

ab

[Robert_Lay]

Dear ab,

My Powershot G5 has a footnote on the page in the users guide that explains shooting movies. I'll bet your camera has the same note. It says, basically, that whatever the Autofocus and Autoexposure controls see on the first frame of the move, that's what you're going to get for the duration of that movie.

So, the best way to set up a movie is to start the movie while set on an object that is at the median distance for your entire movie and and is at a nominal level of brightness for the entire movie - otherwise you will not have optimum focus and exposure.

Obviously, if there are to be portions of the movie in bright sunlight and other portions in deep shade or indoors, then it would make sense to break your movies into shorter clips, so that each clip is shot with a reasonably consistent set of distances and scene brightness for that segment.

Does that make sense?