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Old Jan 14, 2005, 5:32 AM   #16
NHL
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BobA wrote:
Quote:
I believe that FE lock isn't linked to the "active" focus point, but to the "partial metering" area in the middle of the viewfinder.

AE lock is linked to the active focusing point.
I noticed this too if you mean by AE lock is performed by holding down the camera shutter 1/2 way...

... and FE lock with the * button is "partial metering", I saw this documented only in the 300D/DRebel manual but none on the other cameras, but I concur with your results here



Quote:
"E-TTL II is never linked to the active focusing point. In fact, that is one of the main differences between E-TTL II and the original version of E-TTL."
This is not a very accurate info, they are both link to the active AF point: Whereas the E-TTL looks at the luminosity of the object(s) around the active AF point, the E-TTL II get the distance info from the lens to the object picked by the active AF area and determines its exposure ignoring it's brightness value - This is very similar to the old day when one determines an exposure (aperture) value by dividing the Guide Number to the subject distance... (or change the power setting of the flash by keeping the aperture fixed).
Of course E-TTL II can't get this info on older lenses, like my 85mm f/1.2 or if the AF/M switch on the lens is switched to manual where it'll revert to E-TTL!
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