Great lens for nature and wildlife photography

I love this lens! I first rented one for a trip to Alaska, and it took wonderful pictures under less than ideal situations - on moving buses, boats, and even from an ocean kayak in light swell. I finally broke down and bought one recently.

Image stabilization is superb. Prior to focusing one can see the image shaking through the camera's (T4i in my case) viewfinder, but the image stabilizes almost instantly with a half-depress of the shutter button. This is not to say one will not ever get blurry shots, but this lens does an amazing job even at 400mm without a tripod/monopod. Images are very crisp in the 100-300 mm range, but can be a little "soft" at 400mm. Still, I regularly look at my photos on a 27" monitor, and I am very pleased with the image quality, even (especially!) at full lens extension. I have not tried to print any of my photos, so I can not address print quality.

This is not the fastest lens in the world, but it does not suck either. Putting a circular polarizer on it almost guarantees an ISO bump unless you are shooting in very sunny conditions. With just a UV filter on the lens last weekend, I was able to shoot 1/640, f/4.5, ISO 100, 400mm under completely overcast conditions and got many very clean pictures, including moving seals and birds in flight.  I shot very acceptable pictures of a full moon at 1/1250, f/5.6 ISO 400, 400mm, although a tripod was required for this.

The zoom function is a little unusual - it is a push/pull system that takes a little getting used to. It's quick and easy to change focal lengths if one leaves the locking ring a little loose. Within half an hour of my first using the lens I was changing focal lengths quickly and with little thought.

The lens is a little heavy, but this is to be expected given what the lens does. I would not recommend hanging it around your neck for extended periods of time.

Overall I have been very happy with the overall performance of this lens. That being said, I highly recommend renting this lens and trying it out before buying it. There are a number of very good online-companies (not sure if DPReview will let me post URLs) that rent this lens for relatively cheap (~$60 for a week, plus ~$25 shipping).

I'm glad you liked yours. I've owned one and have since sold it. To be fair, I had an early version with Canon's original IS technology. While I can't say for sure, but it appears that lenses made after 2008 or thereabouts or significantly better than older ones.

Mine was dreadful in early morning light. My first experience with it was shooting birds in flight (BIF), which itself it difficult. In low light conditions, early morning, the lens was almost impossible to auto-focus. Eventually I went to manual focus set at infinity and hoped. This was true while shooting with the 50D. I've since tried it on a 7D and borrowed one on the 5D Mk III with similar results.

This is a lens Canon needs to update. My only concern is that whatever they do to the lens, the retail will be too close to US$ 3,000.00 for my wallet.

Enjoy and good shooting.

Its also a great birding lens with the 7D and very hand holdable! Its a great back up for my 500 II.

Here is a link to a set with the 7D and 100-400 L

http://www.flickr.com/photos/40906945@N08/sets/72157638832098013/

Cheers

The same from, since I'm more in wildlife, they on on my 60D as a default, just one latest sample. handheld: