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suse
24th of June 2005 (Fri), 15:35
Hi

I just received my new 24-70L. I was beginning to think I had a good copy, until I did a brief test. I'm not a professional, so if anyone can me any tips on assessing new lens, I'd be really grateful.

I took 2 shots at 24mm, f5.6, one autofocus and one manual. Then 2 more at 24mm, f2.8. It was 100ISO. The shots were with a tripod and it was a cloudy day. The one at 2.8 which was with autofocus seemed to come out a little soft, although it seemed to have sharpened up on manual. The point of focus, btw, was the word 'create' across the cover of the magazine.

I've posted the shots on pbase: http://www.pbase.com/phototext/24-70_lens_test

There are two more on at 46mm. I would have taken a few more at 70mm etc, but it started to rain (this is England), so I'll have to wait until tomorrow or Sunday.

Is this still a good copy, with that result? Is autofocus always going to be a bit of a problem at various stages with lens, or should a good copy be consistent throughout. Please excuse the lack of creativity on the test shots; it was a purely functional exercise. Any tips on what to add to the lens assessment or the look of the lens would be gratefully received.

Andy_T
24th of June 2005 (Fri), 17:02
Suse,

the manual focus shot is clearly a lot better.

Did you focus and recompose? That might be a reason for the result.
When doing test shots, you should observe that you shoot a subject at the same height as the camera that is totally parallel (not a leaning magazine).

I would do more tests in a more controlled environment before returning the lens.

Best regards,
Andy