Canon 30D - Manual (Page 6)

Page 6 of 35 © Ken Rockwell 2006
CONTROLS
TOP PANEL CONTROLS
Left side:
Control Wheel: I leave this on P, Program exposure. This lets the 30D select
the aperture and shutter speed, which it does perfectly all by itself.
If I want different shutter speeds or apertures than the 30D's Program mode
selections, I spin the front dial to select other combinations. Easy! Spinning
the front dial in the Program mode is much faster and easier than switching to
any of the other modes.
I'll use Tv ("Time value") if I want to select a certain shutter speed only, in
which case the 30D selects the aperture. I never use this.
I'll use Av ("Aperture value") if I want to select a certain aperture only, in
which case the 30D selects the shutter speed. I only use this when testing
lenses and need exact apertures. I don't use this for real photography.
M is manual exposure. You have to select the aperture and shutter speed the
hard way: with more knobs. I'll only use this if I'm photographing something
weird that requires me to lock down the exposure and keep it from changing.
This most often is outdoors at night.
A-DEP is a goofy mode which is supposed to select the aperture based on
how much depth-of-field you require. I've tried it, and never use it.