sigma 18-50 2.8-4.5 os or canon is

[automaton2]

which of these are the best choice sigma2.8-4.5 os or canon 18-50:cryin:

[Anbesol]

You said two different specs, you listed the Sigmas aperture range and the canons focal range.

However it looks like there is a Sigma 18-50 f/2.8-4.5, but there isn't a canon 18-50, so I assume you are talking about the Canon 18-55 f/3.5-5.6?

If so, the Sigma is slightly faster throughout its zoom range, so you will have a little better shutter speed overhead, and slightly more narrow dof achievable with the Sigma. But, I would advise against both and suggest Tamrons 17-50 f/2.8 instead, its a constant aperture throughout so its much faster than both, especially at the telephoto end. It has much more dof control and will provide faster auto-focus and shutter speed ability. Because its faster, it will also give you a brighter view through the viewfinder. Its also very well priced. Personally, I would not hesitate to choose it over either canon's kit or sigmas 18-50, hands down.

IF the sigma and canon are your only options, I would opt slightly in favor of the sigma for its slightly faster aperture range, but - Sigma has a history of producing misaligned elements and has a history of poor focusing issues. I would be more enthusiastic about the Sigma if you can see the physical item and make sure its all in good working order first.

[automaton2]

thank you for reply I am more befuddled after reading multiple reviews
the lenses you suggested are out of my price range
heres reviews of each
http://www.slrgear.com/reviews/showp...ct/1249/cat/31
http://www.slrgear.com/reviews/showcat.php/cat/31

[Anbesol]

Sorry to confuse you, my personal choice would be the Sigma for its slightly faster aperture range. This allows more narrow depth of field, faster shutter speeds, brighter viewing in the viewfinder, and even slightly improves AF speed and accuracy. The Sigma also has a significantly better build quality.

But I wouldn't sweat it too much, there isn't really much difference between the two, both can be used almost interchangeably, the differences I mentioned are very slight due to only a slight aperture gain with the sigma.

That said, the recommendation I make is assuming that both are equal cost, if the Canon's half the price of the Sigma, I'd go for the Canon. Then maybe take that extra money and get a 50mm f/1.8 to augment.

Anyway sorry if I'm still confusing you, hope that helps.