Exposure issue on 5D3

Started Apr 23, 2012 | Discussions thread
AndreeMarkefors Junior Member • Posts: 44
This IS what is happening.

I have a thread about this as well that was started a few days back.

The camera is working correctly and the user is fooled by.. dare I say bad engineering?

It is the AF-point bias that is causing this.

Although there as been a thorough recap of how exposure and exposure compensation works in this thread, this should be a total non issue on a picture of this kind, when set to evaluative.

But Canon introduced AF-point bias with the 7D (I think?), and it has now made its way to the 5D mkIII.

Why you would want to bias the exposure in an evaluative matrix mode is beyond me. The feature is however excellent in spot mode (not available on 5D mkIII, only 1D...)

I could even live with the feature if it was a tip of the scale between two exposures, but this bias function can get exposure off by 2 stops and even more.

Av-mode is almost useless due to the fact that I have to double check every damn shot.

I think the issue is the plentitude of AF-points that is the culprit. The bias zones become too small and in a flower shot it may very well be that the image is very bright around your small area of focus.

TRY THIS: put your 5D on a tripod, or hold it steady. Aim at a scene with some contrast. Move your AF-point around and see your metering change. It can go from 1/60 to 1/800 in the same evaluative matrix scene.


I posted about a ways to "shut the bias off", but I don't think that is possible, which in itself is an epic fail; at least make it a custom function!!

 AndreeMarkefors's gear list:AndreeMarkefors's gear list
Canon XC10 Canon EOS-1D C Canon EOS-1D X Mark II Canon EF 70-200mm f/2.8L IS II USM Canon EF 24-105mm f/4L IS USM +6 more
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