Do I need a zoom that starts at 17mm?

Jane B.

I am dreaming of a wider zoom lens for my D60. One place that I shoot at my church has me questioning if I can get by with one that starts at 18mm or if I need to go to 17 (Tamron 17-50?). On a film EOS camera 28mm was just wide enough at the wide end (original version of Canon's 28-70 f3.5-4.5). And a friends Nikon that starts at 18 is comfortable but without much leway. So. . . with his Nikon being a 1.5 camera and my D60 at 1.6 I have questioned if one that starts at 18mm would do. But, then again a fellow from my local camera club told me that that 1mm difference just makes about 4 inches difference in where you have to stand and this is a demension that I understand better than degrees. Unfortunatly, that club is heavy on Nikon shooters and another Canon shooter there also has a lens that starts at 28mm as his widest! I know of only one in that group that has the "kit" lens for a 20D and he lives out of town and is here mainly for club events.

Am I right that there is more available at the economy end that starts at 18?

Thanks in advance for your suggestions.
Jane B.

ziggy53

Jane,

The first thing you have to understand is that often these focal length designations are not accurate. It is well documented that zoom lenses, in particular, are often exagerated, and the measured focal length also varies with the distance the lens is focussed to.

http://www.bobatkins.com/photography/technical/measuring_focal_length.html

I would not count on any lens to deliver its "rated" focal length, unless tested in the field by myself or a respected (by me) authority. I found that the long length of my Sigma 18-50mm, f2.8 EX lens was off by 3-5mm, for instance. This is way beyond normal variability, so I would call this lens "marketing measured". In other words, somebody, probably a Marketing person at Sigma, decided that this lens should be an "18-50mm" to comptete with other lenses of that same range, not because of actual measured performance. (Likewise, the Canon 18-55mm "kit" lens has a different field of view at 18mm than the Sigma at 18mm, but I never cared to try to determine if either was accurate.)

What I'm trying to say is, don't get too wound up worrying about 1 millimeter or 2 millimeters. Always test a lens in "your" environment to determine suitability for "your" needs. That means ordering from a supplier than allows returns in case the lens is "not" suitable for your needs (or rent/borrow a lens).

I believe I did read somewhere that the Canon 16-35mm, f2.8L lens did test pretty well against known fixed focal length lenses, but I only found this comparison and review to show it is wider than the 17-35mm lens it replaced.

http://www.luminous-landscape.com/reviews/lenses/16-35.shtml

ziggy53