For the money this is a great lens. I have a cannon 80D and have ...
930295
Wow! For the money this is a great lens. I have a cannon 80D and have used this lens for stills as well as video, the auto focus is a little noisy but 90% of the time I shoot with a wireless mic so not an issue for me. I would highly recommend picking up one of these guys... I would buy again in a heart beat.
616295
Though this is my first lens I have done a lot of research on which to get. It makes me knowledgeable about the lens. I have owned it for about 3 weeks now. I shoot with a Canon 40D. I can say that this lens is excellent for its price. It's constant F2.8 aperture makes it so that you can still do zoom adjustments after focusing, making this lens very fast to work with. Depth of field range is excellent. F 8.0 seems to have the best balance. The build is pretty solid as well, no rattling components, no loose ends. However my only complaint with it is the auto focus motor. It is very loud, Think of a small hand drill. They made no attempt to dampen the noise either, though I suppose it cuts the price down to make it competitive. Just don't go around trying to shoot wild life with this. It scares the bejesus out of everything.

Note a few important things before buying this lens:

It is a crop body lens, this means you can't use it on any version of the 5D or 1D without vignetting.

There is a VC (Vibration Compensation) and non-VC model. In my opinion you do not to control shake in the 17-50 range, save money and go with non-VC. (this page is non-VC)

Very nice night lens, while you aren't going to expose the Milky Way, at F 2.8 you get a very good low light setup.

Really, the autofocus motor is loud, the loudest I've heard on a lens yet, keep it in consideration if you shoot nature.

I can answer any other questions if you email me at rcman50166 at yahoo dot com.
3992665
I think bang for the buck this is a great tilt shift lens. My only reason for not giving it 5 stars is that the lock screw knobs are very small and can be a little hard to turn. Not sure why they didn't use larger ones like they did on the adjustment knobs. However, it is a tough durable lens with excellent optics.
2531947
If you are looking for an inexpensive telephoto, this one will work out well in most situations.  At 300mm it's a little slow @ f/5.6 so you may want to consider a monopod or tripod.  Also, the image starts to get a little soft at 300mm.  That being said, I have taken some great photos with this.  I also use the lens with my equatorial mount to take astrophotos.  I was able to get lots of deep sky objects with this lens at 300mm.  I recently captured M101, M5, M27, and M38.  Sure, you can buy a sharper and faster lens, but it's going to cost you a lot more.  This is a very versatile lens for the money and a great entry level telephoto.
3359121
I bought this lens for it's low light capabilities and I was not disappointed. I used it for inside shooting w/out a flash and "freezing" action in good light like hummingbirds. Very "fast" lens. I eventually sold this for it's slightly sturdier and a little faster cousin the Canon 50mm 1.4. Honestly I don't see a huge  difference. This is a good bang for the buck lens.
4542340
This lens is great!

I keep thinking I need to be holding more weight or listening to focusing noises.

The weight had me worried, but my&nbsp;<a data-hook="product-link-linked" class="a-link-normal" href="/Canon-EF-S-17-55mm-f-2-8-IS-USM-Lens-for-Canon-DSLR-Cameras/dp/B000EW8074/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Canon EF-S 17-55mm f/2.8 IS USM Lens for Canon DSLR Cameras</a>&nbsp;is just as heavy.  This lens balances perfectly, and is virtually silent.

At $650 for an L Class 70-200 zoom...  WOW.

Probably one of the best bargains out there for Canon users.  This lens is very nice.

I was also expecting my photos to be blurred, but I've had nothing but great results hand holding the lens at f4.  Once it is tripod mounted, then you are set.

5/5 for sure.

-Update 8/15/2010-  This lens STAYS on my tripod at home.  It is GREAT for the wildlife in my backyard / patio.  It makes a great portrait lens, it does MANY, MANY things well.

Get ready for "Can you see (________) from here with that?" comments.  A big white lens stands out like...  a big white lens...

Hope my ramblings helped.
3643433
This is a great lens if you want to save a little bit of money from the bigger name brands.
758147
This lens does the job I expected it to do. I have a Canon T1i with two standard lens, the 18-55mm standard lens and a 75-300mm. There are times when I want a wide angle and this lens on the standard lens set at 18mm is the equivalent of an 8mm lens. Gives a 90 degree field of view in the horizontal direction. There is some chromatic aberration near the edge of the field of view and well as curvature, but I expected this and is only really noticeable when you enlarge the edges of the image. It does not detract from the images taken with this lens. I am pleased with the images produced in the wide angle mode. It does attach to the 75-300mm lens and I have used it on occasion and by setting the lens between 125 and 160 the wide angle lens gives me focal lengths of about 55 to 72mm, filling in the distances between my two main lens

When the front part of this two element lens is removed you have a very nice macro lens that produces excellent macro images with either of my standard lens at any focal length. Great close up images of flowers, insects, what have you.

Overall I rate this lens very high, excellent price and really two lens for the price of one. Will also rate the seller, Big Mike, as excellent and with very fast standard shipping.
2421452
I really have been pleased with this lens. The pictures I took were clear and sharp. I gave this lens four stars because it's auto focus was a little on the slow side. It's manual focus was quick and easy to use. I came close to not ordering this lens because of some of the negative reviews. I am glad that I didn't let them discourage me. Now that I have purchased, and used the lens, I see those negative reviews as a little on the harsh side. I have used this lens to photograph college, and minor league professionalbaseball, and for some pictures of birds.  I would recommend this lens too others who are in need of a good telephoto lens like this, and have a limited budget.
4807173
This is a wonderful lens. It is easy to use and works wide angle to normal lens easily. I have used this lens for more than a year,I shoot roughly 1500 frames a month, so I have used this lens a lot with no problems.
3573748
This is a great lens for money. I'm not a pro, but like having different lenses for Nikon camera and didn't want to spend a fortune on the Nikon brand lens.
581978
I am not a professional but this is a great lens you can beat it for the price.  Definetly works as described.
209797
This lens is a great deal for the price.  Granted it can feel a little cheap because it is mostly plastic but you can't beat the fact that you have a f/1.8 for pennies on the dollar.  I recommend this lens for any person that needs to add some versatility to their camera bag.
140858
This lens is great for the price.  Does exactly what it is supposed to. Comes with a great storing case. You could probably get a little better picture with a dedicated wide angle but I doubt the average person could tell one from the other when viewing the pictures.
1786881
First of all, this lens is completely manual.  The aperture controls of this lens are on the lens and are not accessible on the camera.  There is no metal ring for the camera to control the aperture of this lens.  I knew this before I purchased this lens so I was fine with this.  If you have a camera that does not meter through the lens you will not have metering (like crop sensors D5300 etc).  When you make the aperture smaller from the aperture ring of the lens the view through the camera gets darker.  So, at this point you will have to take a few pictures to make sure you are in proper metering.  No big deal with a digital camera.  The lens is big and sort of square.  I have a D600 and I can get to everything on the lens though it does get a little tight.  There is a lot of cool stuff you can do with this lens.  Just search tilt shift on youtube for examples.  Compared with the $2000 price of the Nikon tilt-shift this is a very good option.  If you have the money this is a good lens to purchase.

The only problem is the lens cap.  It always seems to come off when I open my bag.  The springs are not that tight compared with the Nikon caps.  The Nikon 82mm Caps are $25 so plan on that.
676483
If you know what this lens is and what it is capable of, it is a great lens. This lens is a great way to see if you want a huge tele lens without a huge investment. When the light is perfect and the subject is still, the quality is very high considering the price. It gets really weak under low light, but the for the price it is great. It is also well built-all metal casing and real glass. It works great as a telescope and I have captured some good moon shots with it. I recommend this lens, but read up on what it is and what it is not.
1342707
Dont let this lens fool you.yes, it's plastic on the outside and glass on the inside. But it is of very high quality optically for the price you will not be disappointed I spent more on the Canon 40D with the 28-135 kit lens with IS and even on the sharpest settings this camera the A200 and 75-300 F4.5-5.6 smokes it in image quality  the 300 end is a little soft but if you stop it down to f8 it sharpens up ...Not as sharp as the 70-300G ssm but a good budget lens until you can afford the  G LENS