equipment recommendation - How do I choose a telephoto zoom lens?

I have a Canon 1100D kit (18-55mm IS II) and a 50mm f1.8 lens. Now I'm looking for a zoom lens. What do you think about the following:

• Tamron 18-200mm f3.5-6.3


• Tamron 70-300mm f4-f5.6 DI LD


• Tamron 55-200mm f4-f5.6 DI II


• Canon 55-250mm IS f4-f5.6



• Canon 75-300mm f4-f5.6 III


• Canon 75-300mm f4-f5.6 III USM

I really don't know what I should chose. I tried to compare on dpreview.com, but I'm not so sure that I have the right lenses in the comparison, since in the store that I want to buy the name doesn't contain some letters, like this: Tamron AF 18-200mm F/3.5-6.3 XR Di II LD Aspherical (IF) Macro is the name in the comparison, but in the store is the same name as the list.

Here is the link: http://www.dpreview.com/products/compare/side-by-side?products=tamron_18-200_3p5-6p3_di_ii&products=tamron_70-300_4-5p6_di&products=tamron_55-200_4-5p6_di_ii&products=canon_55-250_4-5p6_is&products=canon_75-300_4-5p6&products=canon_75-300_4p0-5p6

Answer

In most cases, you're going to want a lens that complements the lens(es) already in your bag. In your case, any of the lenses in the 55-250 / 70-300 range would accomplish this.

The 55-250 is a decent entry-level zoom. For the money, it's a good complement to your kit lens. Canon's 75-300 is generally not very well-liked, but for a little more money, their 70-300 IS USM is considered pretty decent -- sort of in-between the 55-250 and their low-end "L" lenses.

Based on the lenses in your list, I'm going to assume that you're trying to keep to a pretty strict budget. If that's the case, I'd recommend the 55-250. Take good care of it, and you'll be able to sell it later if you want to move up to a better lens.