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darklord
08-17-2010, 09:47 PM
I've got a theoretical question about average and good lens. Let's compare the kit 18-55 lens and the premium 17-55 f/2.8lens.


My question is thatin landscape shooting when small apertures are used, would the differences between these two different tiers of lenses become not as noticeble? Thanks.

neuroanatomist
08-17-2010, 10:00 PM
Not as noticeable, yes. But I suspect, still noticeable.

czeano
08-17-2010, 10:10 PM
Judging on similar comparisons between lenses from Canon, the 17-55 has higher quality components and higher precision in assembly than the 18-55 kit lenses. Even at small apertures (which "mask" a lot of lens defects), the 17-55 ought to be brighter, sharper, and have better saturation and less distortion.


http://www.The-Digital-Picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=455&Camera=474&Sample=0&FLI=2&API= 3&LensComp=398&CameraComp=474&SampleComp=0&FLIComp =2&APIComp=3


This mouse-over comparison has the two lenses at 28mm (a length not common for landscapes, but common to both lenses), f/8 (which is the threshold after which you'd start seeing diffraction influence at a 100% zoom on most current Canon bodies). Even taking into account minor errors in camera and target alignment (which Bryan goes go great lengths to avoid), you can plainly see less chromatic aberration around the numbers in the "Corner" section for the 17-55... although admittedly the 18-55 is a little sharper in the center for that sample.


That said, "being there" is probably more important than nuances gear selection, and knowing your equipment can overcome a lot of differences in equipment.

Daniel Browning
08-17-2010, 10:36 PM
Great posts.



although admittedly the 18-55 is a little sharper in the center for that sample.


I think it only seems that way because the 18-55 has more distortion, which makes the center larger than in the 17-55. But even at the smaller size, you can see the 17-55 has a lot more colored artifacts which are caused by high frequency detail, so I would say it's sharper even in the center.


Another advantage of the 17-55 is flare.