Stephen Melvin said:
jrista said:
Well, metering, at the very least, will always occur. Even in M mode, it is essential so the camera can handle nuanced changes in lighting and still expose according to the settings you choose. You can move AF start to a different button, and only activate AF when you want to...that might help improve burst rate to some degree.
"...it is essential so the camera can handle nuanced changes in lighting and still expose according to the settings you choose."
Let's say my settings are ISO 3200, 1/125 at f/1.4. Those remain absolutely consistent, because I've set my exposure and don't need the meter anymore. No matter what the meter reads, my settings are ISO 3200, 1/125 at f/1.4. I'm in manual mode. The meter should have absolutely no bearing on the speed of operation of the camera. That it does is absurd.
Well, not really. Actual ISO settings, vs. selected ISO settings, are not always the same. The camera has to account for light transmission differences in each lens as they are not all the same, and different element types transmit light differently. Diaphragms don't always stop down "neatly", and the actual light that passes through them is not as entirely uniform as one would think given the "ideal" settings available in the camera. Most Canon lenses are chipped to provide the camera with statistics about exactly how they transmit light, and the meter is still used to make fine adjustments to the actual ISO setting that is used when you expose to account for small differences. Even taking all those extra nuances into account, an advanced camera like the 7D still can't always correct deficiencies in specific lens designs. Some lenses always under or over expose by around 1/3rd of a stop on some cameras, while on others they may expose exactly correct.
If you were to take 10 shots of the same scene, all 10 shots probably wouldn't come out exactly identical. Even if they appeared identical, if you were to do a scientific measurement of the ISO of the shot based on the RAW pixels, its doubtful it would always come out at exactly 3200 or even be the same every time. The camera is still doing a lot of work behind the scenes to help your exposures come out as "correctly" as possible.
