I use an A710, but I guess it may apply to most Canons...
I was shooting in Av mode, like most people, to keep the aperture at f/4. But I then decided to test P mode to see what combinations it was selecting for various lighting levels.
What I found is that the camera will select f/4 for speed of 1/60 and faster. As light levels drop, it holds 1/60 while opening the aperture. Then, at f/2.8 it will start to extend the speed.
I thought about that for a moment and concluded that it's close enough to perfect. So now I'm shooting in P mode. This allows me to press the EC button after turning the camera on, and leave the camera in EC and not have to worry about opening the aperture in a low-light situation.
So I recommend testing your P mode to see if it selects the same combinations that you would select in a range of light levels.
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I was shooting in Av mode, like most people, to keep the aperture at f/4. But I then decided to test P mode to see what combinations it was selecting for various lighting levels.
What I found is that the camera will select f/4 for speed of 1/60 and faster. As light levels drop, it holds 1/60 while opening the aperture. Then, at f/2.8 it will start to extend the speed.
I thought about that for a moment and concluded that it's close enough to perfect. So now I'm shooting in P mode. This allows me to press the EC button after turning the camera on, and leave the camera in EC and not have to worry about opening the aperture in a low-light situation.
So I recommend testing your P mode to see if it selects the same combinations that you would select in a range of light levels.
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