Sigma 18 - 50mm EX DC Macro

I'm a bit frustrated w/the Canon 18-55mm kit lens that came w/my XTi. The focusing ring "shakes" when the wind blows and fails to hold focus. Sooo, I'm looking at the Sigma as an upgrade. I've got a Sigma 18-200, Tamron 17-50 and Sigma 10-20. I'm not impressed w/the Tamron's auto or manual focus. Plus, I don't have a macro ability on any of these. I'm an Earth, Sea and Sky photographer: landscapes and nature only and many photos at sunrise where I hope an f2.8 will help. I've read several positive reviews on the Sigma 18-50 Macro but wonder if any real people have had any experience w/this lens and (2d) if it's really going to compliment the lens collection I already have. I'm buying lottery tickets every week but so far can't afford the Canon version so let's not try to convince me to spend the extra $700.

I have the Tamron 17-50 2.8 and it works great and focuses very quickly. Not sure what might be wrong with yours. Why not send it into tamron for them to check it out?

Jim

I have the Sigma 10-20 and 18-200, as well. I also have the Sigma 70-300. All three of these lenses have given me excellent results with no hassles. Can't speak personally for the 18-50 macro, but the information available by "googling" is mostly all positive. Personally, I would not hesitate to buy the lens. Last I heard, Sigma remains in the unique position of producing all its resins, glass, etc. for all their products, so they have complete quality control. It shows in their cameras, flashes, and lenses.

If you are looking to do serious macro work, there is no substitute for a prime lens. Sigma's 50, 70, 105, 150 and 180 macro lenses are well respected, as is the Tamron 90 as far as third party lenses are concerned. I have experience with the Tamron and the Sigma 150. Depending on the type of work you intend to do, you might benefit from the extra working distance provided by the 150 and the 180 mm lenses. One thing to keep in mind, that in order to make internal focusing work on these lenses, the manufacturers shorten the focal length at the closest focusing distances, which means that your working distance would be shorter than a Nikon or Canon lens at the same magnification when used at very close distances.

One thing about the Sigma 150 - while it has impeccable sharpness and extremely high overall image quality, the bokeh could be better, as it is a little distracting. Some users have reported that the autofocus is slow. If you are using it in full range of focus mode, then to go from 1:1 to inf will take a bit. The lens does have focus range limiting so that you can get better control over this. I have successfully used it in sports and other situations without issue. Hope this helps.

I had the Tamron 17-55 and thought it was a great lens. I only sold it because I sold my XTi. I'm sure that the Sigma 18-50 lens is probably in the same league and I don't think you'll be disappointed in it. Keep in mind that the Sigma isn't a true macro lens. It only has a maximum magnification of 1:3 which is good for close ups but but not really true macros.
Also, I'm not sure how f/2.8 will help you with sunrise landscapes. For sunrise landscapes I use an aperture of f/11 and up and always use a solid tripod. A shallow aperture won't get you the depth of field you're after.

I used to have the Sigma 18-50mm when I owned a D20. Very good lens, built like a tank. Unfortunately, it is neither wide, nor long for a D20. I then switched to a Canon 10-22, which I must say was the best lens I've ever used. Even the 17-40 or the 16-35 on the 5D doesn't compare with the 10-22 on the D20.

Thanks all for your comments. I have gear-head disease and thought that the Sigma would help improve my photos. As much as I hate to admit it, maybe my problem's not with my gear? :) Thanks again.