Accuracy in metering

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Is there any difference in the accuracy in metering a particular subject by a pro EOS 3/1V, midrange EOS 30/33 and the low end EOS 300/3000. For instance, if EOS 300 gives a shutter speed and apperture of, say 1/180 sec and f/8, in a some custom mode, then will EOS 30 or 3 give anything different for the same subject. Ofcouse, EOS 3/1V is capable of changing the EV in 1/3 stops. This will anyway increase the accuracy in metering. In other words, are the light sensors better (in terms of accuracy) for high end bodies.

-- sajeev (chack74@yahoo.co.in), February 28, 2002

Answers

If you use the same subject with the same lighting using a compatable metering mode (9.5% partial or center weighted average) the metering should be very close.

If you use evaluative it may be different because the number of metering segments is different which could cause the algorithms to come up with a different result.

-- Dick Tope (RTope@yahoo.com), February 28, 2002.


Yeah, what he said.

The other thing to keep in mind is low-light metering accuracy; the higher-end bodies usually have meters that work in less light than the lower-end bodies do. Not a big deal for most shots for most people, since if it's that dark, most people will be using flash rather than ambient light.

EOS shutter speeds and apertures are semi-stepless - while not truly stepless, they are controlled to much more precision than the 1/2 or 1/3-stop increments you see on the display. See http://www.chem.helsinki.fi/~toomas/photo/experiment-2.html and http://www.chem.helsinki.fi/~toomas/photo/experiment-1.html for evidence.

-- Steve Dunn (steved@ussinc.com), February 28, 2002.


I have two older A2E's (EOS 5's) as well as a fairly new Rebel 2000 (EOS 300). I've checked their meters against each other and not found there to be an discernable difference in the exposures based on a test target.

-- Lee (Leemarthakiri@sport.rr.com), March 01, 2002.

There is some difference, but it's at the extremes of the ranges. In more difficult situations, a more expensive body will come up with a better value. For example, my new EOS 3 can give me very accurate readings in situations where my EOS 5 wasn't quite so good. In most normal situations though, there isn't a great deal of difference.

-- Isaac Sibson (isibson@hotmail.com), March 02, 2002.

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