haven't checked this one out, but 18-50 is a good range, and f/2.8 is solid too. I have the Canon 17-55mm f/2.8 IS USM and I love it, so if the sigma is anything like that then it should be great.
Another lens that I would strongly recommend is the Canon 50mm f/1.4. Even though it doesn't zoom or anything, it's supposed to be one of the most 'universal' lenses and falls within your price range. I didn't buy one when I bought my T2i and I regret it.
What kind of lens are you looking for? Prime? Zoom?
I will always recommend buying a 10 dollar eos->nikon adapter and buying some cheap nikon primes. 50mm 1.4 is under 100, 20-28mms are 40-100 bucks and you can get a 135 for under 50 bucks and 85mms are about 100 bucks.
if you're trying to get a zoom check out what the other posted, sigma 18-50mm 2.8 ( i think?) and the canon 17-55 2.8.
Sigma 18-50mm 2.8. You can get a discontinued model for less that what you said.
As E-heath stated, you can get great deals on primes. That's for dang sure.
Personally, I have a 50mm Super Tak, a 18-50mm 2.8 Sigma and a 70-200mm 2.8 Sigma. The Super Take rarely leaves my camera bag anymore. I find it must easier to film with a constant aperture zoom lens than switching between primes.
However, this is just my own opinion.
The differences in picture I find can be tweaked by using different picture styles in the T2i. Primes are great, but in certain situations for my case.
if hes filming surfing hes gonna be on a tripod. and if hes taking pictures of surfing its gonna be relatively sunny, and a relatively fast lens. not necessary, and the non is is literally half the cost.
there's a certain point where it neither looks good nor functions properly...that's when you know you look steezy - no_steeze
this lens is kinda meh because the aperture changes as you zoom. plus the aperture isn't that low to begin with, meaning you can't get a super shallow depth of field and it's not great for low light. if it comes with the 7D in a kit then it's solid, but I wouldn't buy it on its own.
I have this camera as well, and I'm wondering how to get a smooth zoom by turning the lens. so most people who film primarily with this get a motorized zoom that's smoother? any other recommendations for using this setup? I have an 85 mm for surf shots and a 35 mm for everything else.
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