larry_rotta

I've noticed that using my newly purchased 70-200 2.8L for portraits (at f3.5), it is quite difficult to get the entire face of the subject *razor* sharp due to the seemingly very shallow depth-of-field that this lense provides.

I was previously using the older Canon 35-105 3.5 (with my AE1) and had no problems with getting the entire face *razor* sharp.

 

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Should/is there a difference between the f3.5 of the L lense vs my older lense at f3.5?

When focusing with the Canon 70-200 2.8 L lense, is it better to zoom in on the subject, focus, zoom out and then take the picture OR is it best to obtain focus at the focal length being used to take the photo?

 

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The reason I ask this question is because I've noticed that when I obtain focus at 70mm,...and then zoom in (200mm)...the lense requires re-focusing.....and then when I zoom back out to 70mm I again have to re-obtain focusing of the subject.

 

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I'm using centre spot focusing, f2.8, and focusing on the same point of the subject each time I focus.

 

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Is there something wrong with way I'm focusing, the lense, or the camera (EOS 3)?????

The EOS3 manual suggests the metering mode be set to SPOT metering while performing FEL (flash exposure lock)using the 550EX flash. I would like to know if FEL will work in other metering modes, such as EVALUATIVE and CENTER WEIGHTED. I am presume the answer would have to be 'yes' since the 550EX flash reads the light coming from the ACTIVE focusing point during 'P' (program) mode.