Can't decide

[ignatiusjk]

I want to get a new lens for my Canon 500D and can't decide between the 18-135mm,or the 18-200mm or the 17-40mmL series lens.I mainly do landscapes so image quality is imperative.The L series seem VERY good but I like the flexibility the 18-135 or 18-200 gives me.Plus the price is much different.What do you think? Is there really that much difference between the L series and the 18-135 or200mm.I currently have a 28-105 lens and it does ok but I want a wider angle.What to do?

[KCook]

For landscapes I would cross off the 18-200. The 18-135 lenses will be Ok, so long as you stop them down. Of course the 17-40 L is a full frame lens (all "L" series are FF). So the 17-40 would be a natural if you expect to eventually move up to a FF body. Another nice "sort of wide" general purpose zoom is the 15-85. For really wide angle I got a Sigma 10-20 f/4-5.6:

Sigma Lens: Zooms - Sigma 10-20mm f/4-5.6 EX DC HSM (Tested) - SLRgear.com!

It pretty well holds its own against Canons, but it is more modest aperture. To get some sense of how this works for landscapes (and what you will be missing below 17mm!) you can check my field of view examples -

Zenfolio | Kelly Cook | Fields of View: 10 - 135 mm

Kelly Cook

[ignatiusjk]

My main concern is the difference in quality between the regular lens and the L series lens.The 18-135 is not an L series lens,but the 17-40 only goes to 40mm not 135.I don't care about shooting full frame since alot of times I shoot "loose" and correct it in Photoshop.So it now comes down to the 18-135 or the 17-40L. I'll have to go through my photos and see how many were shot at wide angle vs tele.I'm leaning towards the 17-40L.My question is how much difference in quality is there between the two lens.If the 18-135 is close to the L lens then I'll go with the 18-135.

[KCook]

I change lenses when I need 135. With a crop sensor Rebel 40mm lens field of view is equivalent to 64mm lens on a FF body. "Full frame" does not mean un-cropped, it means the old 24x36mm format from 35mm film days. FF bodies such as the Canon 5Diii and 6D still use this size sensor. The Rebel uses a smaller sensor, which reduces the field of view by a factor of 1.6 (thus 40mm becomes 64mm). There are lots of images with all of these lenses shown on the Flickr and Pbase photo hosting sites. Dig around and both give you a way to search through their images by lens model.

Kelly

[Andy Stanton]

If the 18-135 is close to the L lens then I'll go with the 18-135.

Most reviews of the 18-135 say it's OK, but not great. This website's review of the Canon T3i, which is bundled with the 18-135, included a section on the performance of the 18-135 lens. As you can see the review is mixed.
Canon EOS Rebel T3i: Performance

[ignatiusjk]

I think I'm going with the 18-135mm lens. I don't like that the 40 has a constant f4 aperature.What if I need to stop down to f16 or 22.My current 28-105 seems to take some very clear pictures so the 18-135 should be at least as good. I also tend to use the "sharpness" filter in photoshop to improve sharpness and I usaully use a tripod as well.Thanks for the info.

[KCook]

The tests online indicate that the 18-135 will have a little higher resolution than the old 28-105.

Kelly