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.

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

-- Larry Rotta (Larry_Rotta@ismbc.com), October 28, 1999

Answers

You may be confusing sharpness and depth of field...

The two lenses overlap only in the 70mm-105mm focal length range. In that range, the maximum aperture of the 28-105 is f/4.5 (not 3.5). The 28-105 @f/4.5 will yield more depth of field (and maybe the perception that it is sharper) than the 70-200 @f/3.5, but I assure you that the 70-200 is sharper, even at f/2.8!

I recently posted some scans of a test I performed between 3 Canon mid-range zooms (including the 28-105). I substituted the 70-200/2.8L for the 28-70/2.8L in the test for focal length greater than 70mm. At the bottom of the page, click on "close-up details" (frames 1-15): http://www.kjs l.com/~dave/lenstest/lenstest.html

-Dave

-- Dave Herzstein (dherzstein@juno.com), October 28, 1999.