Best contrast and resolution lens I have ever used
Very well made
Weather sealed
Very fast focus
Servo tracking work extremely well
IS is the best I have ever used
Flaring is very well controlled.

Lens cap is a pain to use.
Sticks out like a sore thumb
Could be too heavy and too big for over night hiking trips
Looks expensive, both the lens and the lens container

This is the sharpest and has the highest contrast of any lens I have used. The EF 85 F1.2L, 70-200mm 2.8L, EF 100-400mm 4.5L a EF 35 f1.4L just doesn't match in contrast or resolution of the EF300 IS 2.8L. This is particularly noticeable on the human face. This lens displays every detail, imperfections and all. The facial and head hair are as crisp as if I was looking directly at the person. The only other lenses that I have seen that are of the same calibra are those used medium and large format cameras. This lens has excellent resolution starting at F2.8 and only improves very slightly by f4.0. With the 1.4 Extender there is a slight degrading of the image quality and the focus slows a little but it is still far better than the EF100-400. The other features, like the image stabilization and servo focus are the best I have ever come across. I have used the IS to shoot consistently at a 1/40 of a second with excellent results. This, I was not able to do with the EF70-300mm DO IS or the EF100-400mm IS at 300mm.

There are however some drawbacks with this lens, that is, it stick out like a sore thumb even when the large sun shade is removed. People are forever commenting, ”are you from the news paper”, or saying, “what a big lens you have!”. It is relatively heavy and doesn't fit well in my camera bag although I have walked around with it all day without filling too tired. It come in a small car fridge type container that is made very rugged and well sealed from the weather. The lens cap looks more like a leader hat than a cap and is a pain the use. The lens comes with its own strap that I use to carry it around with. I am afraid the the weight of the lens maybe too much for my 5D to contend with and may damage it if I use the 5D's carry strap to support the lens.

The front of the EF 300mm IS f2.8 has no facilities for a protective filter and is possibly too big for any filter that I know of, measuring 11.5cm (4.25inches). The front lens is protected by a glass plate that can be replace by Canon if it gets damage. The optional filters are placed into the lens using a special filter draw located at the rear of the lens. The problem here is with polarizers, it would mean opening the draw, rotating polarizer, closing the draw and checking if it was adjusted correctly.

Overall I am very impressed with its capabilities and only wish that my other lenses could provide such results. It makes me appreciate that I too can get image quality of a medium format digital camera at Canon prices.

Customer Service

not required so far

Similar Products Used:

EF 100-400
EF 70-300 DO

Sharpness, image quality, bokeh

None that I can see

I have had three copies of this lens and all three have been absolutely brilliant.
It is Fast to focus, actually extremely fast and from 2.8 up it is tack sharp.
The IS is a bonus for this focal-length, it really helps when you need to hand hold for shots. As far as weight goes, I am not a big bloke but I manage to hold this lens all day long.
It takes converters extremely well, both 1.4 and 2x and stacked.

Similar Products Used:

120-300 sigma

300mm @ f2.8 is great!
Superb sharpness!
Using my 1.4x I get a 420 f4
Using my 2x I get a 600 f5.6

Price, but you definitely get what you pay for.
Draws some serious attention.

What more can you say about this lens than what has already been plastered on the net? It's white, it's "L" glass, and it really is tack sharp!

Similar Products Used:

70-200 f2.8 with 1.4x and 2x TC's

light weight and compact for a super telephoto. Superior sharpness.

price, you do need the teleconverters for wildlife photography, not long enough for birds (except big tame waterbirds).

This lens is a compromise, which is not a bad thing. Especially since it is a very, very, good compromise. It is light enough to carry and hike with, small enough to go in your carry-on on a regular airliner, long enough for many (not all) wildlife photography tasks, and fast enough to function well in low light, or to keep functioning reasonably well with teleconverters. I find it an especially good "big gun" to take when traveling by air. Picture quality is excellent, even with teleconverters. I do use it with teleconverters a great deal of the time, and many photographers argue that this means the lens is too short for me. I don't agree.

Customer Service

When I needed a minor repair (thanks to my clumsiness), the Canon 800# operators convinced me to send this lens to the Elk Grove, IL repair center. Big mistake on my part! I do not have personal experience in dealing with the other Canon repair centers, but Elk Grove was a nightmare. I ended up spending half my time on a Yellowstone trip without this lens because of repeated delays on Elk Grove's part.

Similar Products Used:

non-IS version of the same lens, Canon 100-400L zoom.

Sharp images wide open at 2.8.

The only weakness is the weight. Although one can handhold this lens, it is difficult to do for more than a few minutes at a time.

This is probably the sharpest mid-telephoto lens I have ever used. THe optics are outstanding. Specifically, the sharpness, colors and contrast are unbeatable. The images are similar from f2.8 to f11. I have used this lens alone and with the 1.4x TC. THere is little if any loss of image quality with the TC. I have compared the images from this lens and the 400mmDO and this lens even with a TC is the clear winner. I highly recommend this lens.

Similar Products Used:

400mm DO, 70-200LIS, 100-400L IS

Solidly built. IS technology.

Switches poorly designed-easy to turn off inadvertently.

A heavy, ultra-expensive lens meant for serious and well-heeled amateurs or professionals. It can be hand held but with difficulty and for short periods of time. The IS technology is quite amazing and permits shutter speeds down to 1/50 sec hand held with very sharp results. Complete review, with jpegs comparing performance with and without teleconverters, and with IS on and off are posted at
http://members.xoom.com/dankstad/istest.htm

Customer Service

Unknown

Similar Products Used:

None.

1) Very sharp slides when handheld and used with 1.4X and 2X extenders (IS enabled). 2) Reasonably small and light considering performance and features. 3) Superbly construction 4) Many useful features 5) Large 2.8 aperture

1) Lens should come with a pouch. 2) It is possible to accidentally hit and change switches on the lens. Needs some kind of lock.

When price is no object, this is the ultimate telephoto lens that can be handheld. You can do without a tripod because of the IS and still allows very sharp images and freeze motion even when using 100 ISO speed film. What other lens gives you sharp pictures up to 600/5.6 (with 2X extender) handheld, allows you to use slow film and freeze motion, and yet light, small and strong enough to be carried around the whole day?

Customer Service

Haven't tried

Similar Products Used:

Canon 35-350L: This lens is much smaller and lighter compared to the 300/2.8. Quality is still very good but needs much

Sturdy built, good sharpness even with 1.4X and 2X converters. Lightweight aalowing it to be used over a long time. Compared to the 400mm 2.8 L USM. Using the 300mm with the 1.4X.

Switches can be very easily changed in position accidentally

Good performance with slow film using IS and converters. For me as a outdoor photographer and specializing in birds the weight as well as the IS is a very good help. Apart from having a fast lens it can be converted in 420mm f4 as well as in a 600mm 5.6. Taking the IS and asuming that you win 2 stops you have a 600mm 2.8 which is incredible fast. After using the 400mm f2.8 for 2+ years I am glad having changed to the 300mm f2.8 IS. Also the 500mm f4 is a incredible tool for the nature photographer.

Customer Service

good

Similar Products Used:

400mm 2.8 L.