06-17-2010, 09:39 AM
[quote name='genotypewriter' date='17 June 2010 - 10:37 AM' timestamp='1276763867' post='579']
Hi Klaus,
Let me start off by saying I'm not a zoom person at all. Not even Nikon's 14-24 or Canon's 70-200 2.8 IS II impress me. So it goes without saying that I have very little regard for the 24-70L.
However, the thing I want to understand better in your review is what should really be blamed for the behaviours that you observed. I understand how you discovered a difference in the field when you focused to infinity... but when considering all things practical, even f/11 at 24mm is enough on a 5D2 to get everything from 2m to infinity in complete focus at 100% view (from my experience). A part of the DOF function, as you know, is the viewing magnification and a 100% view of a 21MP image reduces DOF greatly.
Again, I'm not disputing what you've found here. What would be ideal here is you choosing the perfect/your favourite lens for this focal length (~24mm) and giving us a side-by-side comparison. This way we can see how much blame should go for the lens and how much should go for the DOF.
Also, in all fairness, I think the 24-70L is not that bad, for the zoom it is. If I wanted the best quality for any photographic application, I can't think of any zoom that I might choose over a prime. IQ-purists/aperture-junkies like me aside, anyone who's serious about landscapes wouldn't use this lens either. With the 24-105L IS around, the 24-70L is not the best choice for holiday/"everyday"-shooting either. These points have been established a long time ago and also by your review. So that leaves us with the question: How will this lens perform for the people who want to shoot at f/2.8 in the 24-70 range, against comparable lenses?
Thanks again for the reviews...
GTW
[/quote]
Well, the field curvature issue did show up first on the charts because the corners were completely blurred at f/2.8 on the same image like the sharpest center. Upon defocusing the center towards closer focus distance the corner sharpness increased. This was also the sole reason to take a series of 10-15 shots at the same aperture but at different focus distances and the real world results just reflected the lab findings. So I can only report these findings here.
Field curvature is not THAT unusual - we've seen it in a couple of lenses although few showed a behavior as extreme as the 24-70L.
As far as alternatives are concerned - well, that's not my turn actually. :-)
A 17-55/2.8 on a 7D has certainly better corners than the 24-70L on the 5D II.
The old 28-70L is also supposed to be better than the 24-70L.
Hi Klaus,
Let me start off by saying I'm not a zoom person at all. Not even Nikon's 14-24 or Canon's 70-200 2.8 IS II impress me. So it goes without saying that I have very little regard for the 24-70L.
However, the thing I want to understand better in your review is what should really be blamed for the behaviours that you observed. I understand how you discovered a difference in the field when you focused to infinity... but when considering all things practical, even f/11 at 24mm is enough on a 5D2 to get everything from 2m to infinity in complete focus at 100% view (from my experience). A part of the DOF function, as you know, is the viewing magnification and a 100% view of a 21MP image reduces DOF greatly.
Again, I'm not disputing what you've found here. What would be ideal here is you choosing the perfect/your favourite lens for this focal length (~24mm) and giving us a side-by-side comparison. This way we can see how much blame should go for the lens and how much should go for the DOF.
Also, in all fairness, I think the 24-70L is not that bad, for the zoom it is. If I wanted the best quality for any photographic application, I can't think of any zoom that I might choose over a prime. IQ-purists/aperture-junkies like me aside, anyone who's serious about landscapes wouldn't use this lens either. With the 24-105L IS around, the 24-70L is not the best choice for holiday/"everyday"-shooting either. These points have been established a long time ago and also by your review. So that leaves us with the question: How will this lens perform for the people who want to shoot at f/2.8 in the 24-70 range, against comparable lenses?
Thanks again for the reviews...
GTW
[/quote]
Well, the field curvature issue did show up first on the charts because the corners were completely blurred at f/2.8 on the same image like the sharpest center. Upon defocusing the center towards closer focus distance the corner sharpness increased. This was also the sole reason to take a series of 10-15 shots at the same aperture but at different focus distances and the real world results just reflected the lab findings. So I can only report these findings here.
Field curvature is not THAT unusual - we've seen it in a couple of lenses although few showed a behavior as extreme as the 24-70L.
As far as alternatives are concerned - well, that's not my turn actually. :-)
A 17-55/2.8 on a 7D has certainly better corners than the 24-70L on the 5D II.
The old 28-70L is also supposed to be better than the 24-70L.