Sweet sharp spot for 70-200 IS?

Guys,

Question as above. I did some rather controlled testing of the above lens (tripod mounted manual-focused at a piece of text-laser-printed paper) and found that the sharpest image is at the range of F5.6~F16. Whatever the case, at F2.8, looks softer than other apertures. Are owners of this lens observe the same phenomenon as my case?

Thanks

I much rather spend my time taking quality pictures with my 70-200 lens then running test.
I have no issues with my lens;so why bother wasting the time testing.
Enjoy the lens and take pictures!!!!!!!!!!!!!!
That's what it's for...............

I disagree. If you happen to do some head shots and the eyes are less than sparklingly sharp, by 3.5, with a 1700.00 lens, then I think you've been had.

I'd guess every lens is sharper when it's stopped down a bit. I've not run any tests on my 70-200, but I know at F2.8 it's sharp enough for me. I haven't really tried it stopped down.

The 70-200IS is sharp at 70mm wide open but very sharp at 200mm wide open. The Canon 24-70L is sharper at 70mm f2.8 than the 70-200IS is at that setting. This is all based on not only my findings but according to their MTF charts. It gets slightly sharper up through f11-f14, then afterwards diffraction sets in. It's one amazing lens.

the.digital.guy, you certainly have that right. I like to test my lenses in actual use and find the pros and cons for my style of shooting.

As for the 70-200mm f/2.8 L IS, mine produces great images at my preferred apertures - f/2.8 through f/5.6.

Paul
http://www.iaw.com/~pt​urton/

Someone far more obsessive then even me has already done a lot of lens tests, no need for you or I to waste our time. Now this is someone who has way too much time on his hands.

The 70-200/2.8L IS
http://wlcastleman.com …/reviews/70_200​/index.htm

the site
http://wlcastleman.com​/equip/reviews/

As a note most of the results seem to match my personal experience, however remember that ultimate sharpness may not be a good thing in all situations.