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View Full Version : Sigma 18-200 F/3.5-6.3- a good lens?


Kokuu
12-26-2006, 08:46 PM
I'm looking for a good walk around lens for my Canon Digital Rebel in a reasonable price range (~$500 or less), and upon doing some research and reading some reviews, the Sigma 18-200 F/3.5-6.3 looks like it would be a good lens for my price range. I primarly like to do cosplay photography, especially portraits and headshots. Has anyone had any experience with this lens? Or can you recommend another all-purpose lens that won't break the bank?

SolarTempest
12-26-2006, 10:26 PM
I'm going to recommend against getting this lens. I have a personal preference against lenses that cover a very large range of focal lengths, but for a reason.

It's impossible for lenses to be optimized for very wide (18mm) while still perform well at very telephoto (200mm). In this case, I would expect the 15-200 lens to perform well between something like 20mm and 160mm. At the ends of the focal lengths, contrast and sharpness will likely be pretty low.

If you know how to read MTF charts, check out:
http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3302&navigator=6
I am bad at explaining them...

I have the 70-300mm Sigma and it has a similar MTF characteristic. The ED glass helps a lot, but just don't expect a lot when you're shooting at either end of the lens. That comes with the price I suppose! =P


I'd recommend something with a bit smaller range. What lenses do you already own?

ZiggyB
12-26-2006, 11:41 PM
I haven't had experience with lenses with that large of a focal range before, but the one I'm keeping my eyes on is the Tamron 17-55mm/f2.8 (http://www.tamron.com/lenses/prod/1750_diII_a016.asp). It's a fixed aperture of 2.8 across the zoom range and from what I'm told, quality wise the lens is very solid. Sadly I still don't understand MTF charts, but reviews have generally been positive.

Also it's in the $500 price range last time I checked.

shiroin
12-27-2006, 06:09 AM
It's impossible for lenses to be optimized for very wide (18mm) while still perform well at very telephoto (200mm). In this case, I would expect the 15-200 lens to perform well between something like 20mm and 160mm. At the ends of the focal lengths, contrast and sharpness will likely be pretty low.

it is actually possible, with the expense of size and weight

check out the canon 28-300mmL (or 28-200mmL, forgot which focal length)

its optical quality far exceeds normal zoom lenses and is comparable with professional zoom lenses, but it is a hulk to carry around.

for suggestions i would go for the tamron 17-50 2.8 or the tamron 28-75 2.8

both are great lenses that have recieved good reviews and also very affordable

SolarTempest
12-27-2006, 01:40 PM
I stand corrected!
That 28-300mm IS USM lens is HUGE. With an average price of $2.2k, the design to make it good throughout the range is pretty impressive =)

Still, I read a little bit that the lens is soft at 300 and a bit distortiony at the closest with the widest aperture.


One point I forgot to mention earlier that is you're willing to use the 18-200mm at smaller apertures (F7.1 or F11), it's going to be nice and sharp, pretty much regardless of which focal length you use. During the afternoon outside at cons, it's easy to do this and I use my Sigma a fair bit.