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Canon EF 300mm f/4L USM Lens Review

by Bob Atkins, 1996 (updated September 2007)

This article covers both the old (non-image stabilized) and new (IS) versions of the Canon EOS 300/4. The photos are by Philip Greenspun and were taken with a Canon EOS 5D, (compare prices) (review) for the Africa articles in our Travel section.

Optical Quality

I've tested this lens alongside all the Canon 75-300 and 100-300 zooms, as well as the EF300/2.8L, and it's clear that it is a very good lens indeed. It is significantly sharper than the zooms (including the 100-300/5.6L) and holds its own against it's "big brother" the 300/2.8. It's sharp wide open and even sharper when stopped down to f5.6. I have no hesitation at all using this lens wide open.

Image quality is very close to that of the 300/2.8L. I'd say that the 300/4 at f4 and the 300/2.8 at f2.8 are about equal, but at any given aperture the 300/2.8 has a slight edge. This is based on looking at images of resolution test targets. For real world images, it's pretty hard to tell which lens shot what.

The 300/4L works very well with the Canon 1.4x TC. Again I have no hesitation about shooting wide open (420mm f5.6) with this combinations and I'm very happy with the results. Autofocus is still fast and accurate. In a side by side test of the 300/4L + 1.4x TC and a Sigma 400/5.6 APO (not the new Macro APO), the Canon lens combination was clearly better (shrper, higher contrast, more neutral color).

With the Canon 2x TC you lose autofocus and some image quality. It's a usable 600/8, but I don't think this is a combination you would want to depend on if you were trying to make a living at photography and needed a 600mm lens to do it.

I have also tried the Tamron 1.4x TC with this lens. Results were pretty good, but not as good as with the Canon TC. Autofocus was less reliable, image quality was lower at the edges of the frame and there was slight vignetting wide open.


The lens has a removable tripod collar, a built in sliding lens hood and a USM focus motor with full time manual overide. The front element (77mm filters) does not rotate during focusing. It's well balanced and solidly built (no plastic).

Is it better than the Canon EF400/5.6L?

A lot of people ask this, and my answer is that I don't know, since I've never actually used an EF400/5.6L! I can say though that, in principle, I like the 300/4 + TC combination better than the 400/5.6 + TC combination. With the 300/4 you get excellent 300/4 and 420/5.6 AF lenses. plus a usable manual focus 600/8. With a 400/5.6 you get an excellent 400/5.6 AF lens, a good, but manual focus, 560/8 and a very slow 800/11, which in my opinion isn't a very usable lens.


The EF 300/4L is a killer lens, espcially when combined with the Canon 1.4x TC. It's much better than any zoom I've ever tested at 300mm, and it's 1/2 the weight and 1/4 the price of the EF300/2.8L. It's the lens I take when I'm hiking around in areas where I expect to see wildlife but I don't want to carry too much weight. Not only is the lens pretty light (3lbs), but you don't need a monster tripod to support it either. I've had good results using it on a Bogen 3001 (3.5 lbs) with a medium Bogen ball head. You can't do that with the bigger telephotos. The 300/4 is an ideal compromise of size, weight, focal length, speed and cost

Street price for the EF300/4L is close to $1100 (1/97). A fair price for a used lens in good condition is around $800, but I can't see any reason for anyone ever to sell one. I'm certainly not getting rid of mine!

1997 Update: Canon EF 300mm f/4L Image-Stabilized (IS)

In early 1997, Canon introduced an IS (image-stabilized) version of the 300/4L. The IS lens also has a shorter minimum focus distance. Old questions about the usefulness of IS are raised again by this lens. For example in a May 1997 Outdoor Photographer it was stated that "for many photographers the 300/4L IS lens will replace the need for the f2.8 lens altogether". I'm not so sure.

Just think why photographers use the faster f2.8 lens:

  • Faster shutter speeds to freeze action. IS doesn't help.
  • To blur backgrounds. IS doesn't help.
  • Higher quality optics. IS doesn't help.
  • Due to the above, better performance with TCs. IS doesn't help.
  • AF with a 2x TC. IS doesn't help.

And, of course, once you have the lens on a tripod, IS doesn't help.

IS does help when hand holding the lens, but that's not why most photographers buy a 300/2.8. They aren't going to be hand holding it much. I think few photographers will use a 300mm lens hand held very often. Think about it. Are you really going to take a 300mm lens out in the field and leave your tripod home?

I think the IS lens is a great idea, however don't get sucked in by the hype you may see in the magazines. Given an unlimited budget, I'd get one tomorrow. I might only use the IS function a fraction of the time, but it's nice to have when you need it. Just think about the claims before you rush out and buy one. I own the 75-300 IS lens so I don't have an "anti-IS" bias!. I still much prefer to use it on a tripod when ever I can.

Note that the IS lens has 15 elements in 11 groups, while the original 300/4L has 8 elements in 7 groups. Adding elements can result in greater susceptibility to flare and loss of sharpness. Reports are that the 300/4L USM IS is a sharp lens. However the Popular Photography test (July 1997) seemed to show it was very similar in sharpness to the Sigma 300/4 APO Macro, while George Lepp's test of the original 300/4L showed it significantly sharper than the Sigma 300/$ APO Macro. There really isn't enough critical test data available right now (05/97) to say for sure whether the extra elements in the IS lens cause a slight optical degradation. If the IS function is important to you, that's probably a secondary issue anyway. The IS lens would clearly outperform the original lens in any circumstances in which the IS function was needed (hand holding at less than 1/350). For those using the lens on a tripod all or most of the time, optical performance may be a concern, but we will need to wait for further testing to see if there is a significant difference between the two lenses.

[Editor's Note: Canon settled the question that Bob raised by discontinuing the non-IS version of this lens.]

Canon EF 300/4L USM Technical Data

Construction: 8 elements/7 groups [15/11 for IS]
Angle of view: 8 degrees, 15 minutes
Focus motor: USM
Closest focusing: 2.5 m (8.2 ft) [1.5m for IS]
Filter size: 77 mm
Length and diameter: 214.5 x 90 mm (8-3/8 x 3-9/16 in)
Weight: 1.3 kg (2.9 lb) [1.2kg for IS]

Example Images

Example Images with 1.4X Teleconverter

Red-billed Hornbill. It is tough to fill a significant portion of the frame with a bird with any lens shorter than 800mm.

Example Images with 2X Teleconverter

Springbok captured with 300/4 lens and 2X teleconverter. Note the lack of contrast and punch in the image. It is rarely possible to get a satisfying image with a 2X teleconverter. You are probably better off using a 1.4X teleconverter and cropping.

Where to Buy

The easiest way to buy this lens is from amazon.com.


Text copyright © 1996, Bob Atkins; Images copyright 2007 Philip Greenspun.

Article revised September 2007.

Readers' Comments

Add a comment

Anukul Kapoor , February 02, 1997; 08:32 A.M.

According to a post on the EOS mailing list, a UK magazine "Amateur Photographer" reported that Canon is currently testing a 300/4L with the Image Stabilization feature currently only found on a cheap consumer grade tele zoom. According to the report, the lens should be available sometime this year for just a little more than the current 300/4L.

Sounds like a dream tele lens: light, sharp, usable without a tripod, and less than $2000.

Robert SIlvers , June 03, 1997; 02:14 P.M.

I was photographing a speaker indoors and saw a photographer for the Boston Globe. He also had EOS, and I noticed he was using the 28-70 2.8L from too far away. I offered him my 300 F4.0L to get a tigher shot. He said no thanks, it was not a fast enough lens. I mean, not only was it an F4, but also 300mm which made it 3 stops slower than his lens once you considered the higher shutter speed needed. This comes to my mind on why even though I have the 300mmF4.0L, I also wanted the 300mmF4.0L- Image Stabilized. You can handhold this at 1/30, which gives you three extra stops. Yes, I know that if the subject is moving it is no good -- which is why it will not replace the 300mm 2.8 for sports, but I think there are many cases where this idea wins. Yes, it has 15 elements instead of 8, and for this reason I may not sell my regular 300.

Bill Meyer , August 26, 1997; 02:02 P.M.

I am in love with this lens. The USM is almost dead silent, the fastest I've ever used and the most accurate. I was tracking a redtail hawk from about 200 feet away and it stayed sharply focused at all times using the continuous focus (AI Servo) on my Canon A2.

The slides have been extemely sharp when I do my job. I was at an air show this past Memorial Day and was shooting pictures of the Thunderbirds when I ran out of film (always bring enough film). I had two choices, sit back and watch the Thunderbirds or find a film vendor. I opted for the latter, and after being screwed on the price of grocery store brand Kodak Gold 100 I ran back and shot the rest of the show. I got some awesome full framed shots of the F-16 and had them blown up to 8x12's. To my amazement, the blow ups are extremely sharp and considering the film, I contribute this to my 300 f/4. I would venture to say that I could blow up these images to 11x14 or even 16x20 and still maintain sharpness.

This is the best lens I've ever used and I can attest that it's well worth every penny. No, it's not as bright as a 300 f/2.8 (which is my next desire) but it's f/4 is pretty good and at a substantial cost and weight savings, I'd say it's the best telephoto you can buy.

Paul Tsong , February 17, 1998; 07:09 P.M.

In my neck of the woods (essentially Seattle) at least, it has been my impression (and confirmed in conversation with various salespeople) that this lens is becoming more widely available on the used market as people trade up for the IS version. So if IS is not essential for you, I think good deals can be had.

Harvey Chao , March 07, 1998; 05:09 P.M.

Just a note for anyone trying to track down a copy of the referenced Popular Photography review, it is in JUNE '97, not July as indicated.

Paul Morrison , September 03, 1998; 02:14 A.M.

I have owned both the original 300 f4L and the IS version. I shoot ski action full time and love both of these lenses. I have not purchased the 300 f2.8 due to the performance of the slower, lighter and more versatile f4L's. I replaced the non IS lens as soon as the new version became available. Contrary to the review, the IS lens will make you question the need for a f2.8 optic. No, the IS function will not freeze action directly, but with it's panning mode, it certainly can help. The light weight of these lenses allows vastly easier panning over a 300 f2.8. The small size and light weight also mean that you are much more likely to be carrying this lens than you would the f2.8. The sharpness of the IS version versus the original is a non-issue in my opinion. No noticeable difference. Both excellent. The 77mm filter size is very nice to work with on the smaller 300's and allows smooth filter changes between lenses like the 17-35, 28-70, 70-200 and the 300 f4L's. Perhaps the only negative I can think of regarding the IS version over the original, is that the lens hood on the new version, rubs against the focusing ring when it is pulled back (especially bothersome when using filters, particularly polarizers). Other than that minor quibble, this is a fantastic addition to most any serious photographer arsenal.

Gary Voth , October 07, 1998; 04:44 A.M.

One big additional reason to opt for the 'IS' lens over the standard 300mm f4.0L is the closer focusing distance of 4.9 feet, useful for fashion or portrature where you want a stylized perspective. I now own the 'IS' lens and love it for its light weight and hand-holdability. Optical quality seems very fine. Back in my F1 days I did lots of sports shooting with the FD 300mm f2.8L, so I am familiar with the benefits of having the extra stop. But given how good the 300mm f4.0L 'IS', today I might allocate my "6 pounds" on the 200mm f1.8L or even the 500mm f4.5L...

kurt heintzelman , May 30, 1999; 09:51 P.M.

I recently bought the 300 IS along with the EOS 1.4 TE. Using a 1n and a 540EZ for fill flash when needed,and shooting Velvia w/ a 1 stop push, I have made several trips to the Columbus Zoo, focusing on their outdoor aviary. Simply put, this lens is superbly sharp and the IS technology is astounding. I hand-held every shot through 6 rolls of film (and I shake), and the resulting slides contained a high percentage of keepers. After the first roll or two of film, I added the 1.4 TE, and quickly became addicted to the resulting 420/5.6 IS lens thus created. In fact, the 1.4TE has remained attached ever since! I've previously owned the 400/5.6L, and I honestly feel the 300IS + 1.4TE (in IS mode) delivers far more sharper images. The drawback is, of course, slower autofocusing with the TE attached. This combination will not work well with bird flight or other fast moving subjects. But for slower moving or stationary subjects, the IS lens with or without the TE, hand-held, vastly eclipses the 400/5.6L. As a bird flight lens, the 400 is clearly the winner, but this may become less true with the EOS 3 or the next incarnation of the 1n. After using the 300 IS, I no longer lust for a 300/2.8L or a 400/2.8L. Now I can drool over the 600/4.0L in my wildest dreams...In summary, if you're contemplating a 300/4 L lens, I strongly suggest biting the bullet and shelling out the extra cash for the IS version--you'll be amazed and richly rewarded by what it will do for your telephoto photography. I am not uncommonly getting sharp images at shutter speeds as low as 1/15th sec. in IS mode 1.

kurt heintzelman , June 30, 1999; 11:58 P.M.

The retractable lens hood of my 300/4 IS most certainly locks when properly extended and rotated to the locked position. As for the 2 images graciously provided by Chieh Cheng, I find these images to be rather unsharp and not a good example of what the 300/4 IS is routinely capable of (whether in IS or non-IS mode), in my experience.

kurt heintzelman , July 04, 1999; 06:12 P.M.

At 2.6 lbs., I would certainly not classify the 300/4 IS as an "extremely heavy" lens, as Chieh Cheng asserts. The 400/2.8 or the 600/4--now those are heavy ( approx. 13-14 lbs.) lenses...

I S , October 09, 1999; 06:54 P.M.

I Have just bought the 300 F4 L IS and on present showing I absolutely adore the lens. Since it has taken me some considerable time to afford the lens (#1000=$1600) and considering that I am 17, I am glad to have had good reason for forking out. When I have more results from the lens I shall report again, and perhaps even upload some.

Timothy Breihan , November 08, 1999; 02:42 P.M.

I recently had the opportunity to use a 300/4 L lens on an EOS A2 to photograph a football game (borrowing it while my Nikon equipment was temporarily unavailable) and can say that the lens performed excellently. I had it on a monopod and manually focused the entire time, but the prints were sharp and contrasty, as was the viewfinder image.

To say a bit about the IS version; I am looking at the specifications for the two lenses in Canon's own L lens brochure. The IS lens is slightly larger and heavier (by a mere 25 grams) and adds an additional seven elements in the IS module. It would also appear, by the photo in the brochure at least, the the IS lens lacks a tripod collar, which is absolutely stupid. I suppose Canon thinks that no one is ever going to want to bolt this lens down, but I certainly would not like to hold it for an entire football game!

Speaking of image quality, though, is where the differences in these two lenses make themselves apparent. Canon publishes the Modular Transfer Function graphs of all their L lenses in the brochure, and the results of the new IS lens are interesting. Canon's MTF tests record the resolving power and contrast of each lens at both its maximum aperture as well as stopped down to f/8. There are a pair of results for each aperture, one showing the len's performance with a sagittal target and the other with a meridional target. The more that these lines diverge the greater the len's astigmatism.

The IS lens, while slightly outscoring the original lens in resolving power, had greater astigmatism. In fact, the astigmatism apparent in the IS version at f/8 was equal to the astigmatism of the original lens at f/4. Furthermore, the original lens exhibited virtually no astigmatism whatsoever at f/8.

So, I suppose it is a trade-off. A ten-percent increase in resolving power and Image Stabilization for a fifteen to twenty-percent increase in astigmatism and the perplexing deletion of a tripod collar.

Benjamin Yap , November 08, 1999; 08:33 P.M.

I have the 300/4 IS and mine has a tripod collar as standard.

Timothy Breihan , November 09, 1999; 10:15 P.M.

Very good. I don't know if you have seen the Canon L lens brochure or not, but a closer look reveals that it has simply been removed for the photo, which makes much more sense. Sorry about the mistake!

Rob Schima , February 23, 2000; 05:17 P.M.

I don't own this lens but had a chance to shoot with a friend's recently and was really impressed with it's balance. I use a 70-200L, and the 300 was noticably easier to hold and use.

I still like the flexibilty of the zoom, but this is one aspect of equipment that is often overlooked. I'll be hitting him up for the 300 again in the future!

I S , March 02, 2000; 01:39 P.M.

I'm back again. I'm still very pleased with the quality of results that I have got from this lens. Absolutely excellent. I do have a question though. I received an email from an Abbey at photo.net, asking me about the lens. I tried to reply, but the mail kept getting bounced back. If anyone knows about this, and where I should have replyed to, please email me.

Anyway, about the lens. It is indeed beautifully balanced, and noticeably more weidly than my father's 100-400 L IS, despite being almost as heavy and almost as big. I am finding, however, that I am using up a stupidly large amount of battery power. I seem only to be getting 4 or 5 rolls of 36exp. from my EOS5, 300f4lIS with VG10. Maybe it's due to the fact that I often shoot in the cold, but the camera was never that bad before.

Tripod collars, and a clarification thereof: Canon have two standard removable tripod collars, and some lenses with fixed tripod mounts. The 300 f4LIS, 35-350, 100-400, 70-200f2.8L, 180f3.5L and MPE-65f2.8 all use the bigger, newer collar, whilst the 300f4L, 400f5.6L, 70-200f4L, 200 f2.8L, and perhaps a couple of others use the older, two-piece collar. If the lens does not have the collar on, you can tell which collar it takes by the fact that the new collar uses four small roller bearings on the lens barrel, whereas the old used a large "groove" in the lens barrel. Everybody happy now?

I S , March 25, 2000; 02:04 P.M.

Does anyone else have the same problem I do with cases for this lens? I think very little of the case that Canon supply with the lens, but on a belt system I have no alternative. I use the CCS belt system, but they don't do a lens pouch big enough for this lens. The Canon case fits on the belt system, but I don't like the case (not padded enough, zips could scratch the lens barrel, made of cardboard (check the label if you don't believe me), NOT WATERPROOF.) For a lens which cost #1300 when I bought it, and is #1500 now, it's not enough.

However, there is a possible solution. CCS will custom make a pouch if about 20 are ordered. The pouch could be ordered big enough for 100-400, sigma 170-500, sigma 135-400, 35-350, sigma 400 f5.6, etc. All I need is to find 19 other people who want a belt system case of huge quality (35 year warranty, waterproof, well padded, usual CCS quality.), for a lens of this sort of quality. Please Email me if you're interested. I may be able to get a price by next tuesday, but email me over the next few months if you're interested. I should expect that it will not cost more than about #80 (It's not a lot for a lens which cost so much, remember that.) Let me know, because I can't possibly be the only person out there with this problem

Harvey Chao , August 24, 2000; 01:06 A.M.

A big reason for getting this lens was shooting ice skating exhibitions from the stands, available light and hand held. This lens, in the IS version, has been an absolute JOY! It combines the optical reach, fast autofocus, and sharp crisp images I had been seeking. Using Fuji superia 800, 11 x 14 enlargements are crisp, sharp, and just beautiful! Yes it was expensive, but the results ! Shot some frames at the San Diego Zoo and from a moving tram at the San Diego Wild Animal park - the IS made hand held shots in shadow areas not only possible but practical without having to go to high speed film.

Michael King , December 31, 2000; 08:50 P.M.

I recently bought the non IS version from eBay. The front element has a lot of marks in the coating, from the previous owner's apparent attempts to clean it with a brillo pad! They don't seem to be causing any image problems, though.

I think this lens is just superb in terms of sharpness, brightness and contrast. AF and AI servo on the EOS 3 make this lens a joy to use! The AF is very quick. The build quality is very solid. My only gripe (apart from the coating marks), is its weight. A monopod solves that problem, though.

Hsu Chen-Kuang , April 18, 2001; 07:51 A.M.

I bought a second 300/4L and decide to change it to a 300/4L IS.Why ?

1.I often use 300mm with handhold. 2.Even I use it with tripod,I can shot down the IS function and it works great for me.

So,I think that the 300/4L IS is more suitable for me.

Craig Watson , November 28, 2002; 12:23 P.M.

In Reference to the review of the Canon 300 f/4 versus the newer "IS" version of the lens, I would like to submit one additional consideration. The Original version of the lens was and is Tack Sharp. However, I have heard the Image Stabilization does seem to subjectively improve the quality of the image by off-setting camera vibration (On a tripod) during exposure. As of late I have also heard some really good reports of using the lens with a 2X Canon TC to photograph butterflies.

Daniel Sandlin , December 22, 2002; 01:18 A.M.

I wouldlike to answer the author's question "would yuo really carry a 300mm nto the feild and leave your tripod at home?" Yes I would, and I also intend to shoot wildlife. A lifetime of hunting wit hheavy rifles and shooting at the range of 500 or more yards at the range has taught me to find a good steady rest even leaning on a tree can enable you to pull of a 300yd shot at a running deer. I figure the less gear you pack the better off you are physically. Take it from someone who has spent his life in hard labor, and packing the weight because "I'm the strongest S.O.B you'll ever see!" was brought down by his very arrogance and pride. I switched to EOS from FD to save weight so I could still enjoy my hobby turned livelihood. Just pickup some real cheap print film, or bulkload some black and white and go out to the feild, and practice handholding, and resting off of any available surface. It will take a little practice but you will soon master the techniques. One thing about humans is that we adapt very well to change.Yes you do need a tripod for some things especially lowlight shooting, but it is a cumbersome peice of equipent that can be left in the truch except for when the situation calls. I can't count how many times I lugged it for no reason just to come home wit hmy back wrenched because the extra weight slung across my shoulders and the physical compensation to keep it from falling or getting hung up whe ncrawling over logs or through viney maple. For that reason, I think the 300 F4IS sounds like a treat, if need be you can always turn the IS off and have the benifits of anon IS lens. Very good review and has convinced me to look into this lens as a potential dream lens if I cant swing the 400mm. P.S. I do however always carry a nice sturdy SIMA Monopod.

Wee Keng_Hor , March 31, 2003; 09:34 A.M.

I have both the non-IS and IS verions concurrently for a brief period. Was indifferent to both but later sold the non-IS and keep the IS. Now I was glad that I keep the IS. There are many occasions that setting up the tripod is impractical. With some luck and extra care, I'm able to obtain razor sharp images shooting at 1/20s.

f5.6, 1/20s

Jim Mueller , April 21, 2004; 08:32 P.M.

300D, 300/4 IS + 1.4X TC II at f/5.6, 1/1000 sec, ISO 200 +2/3 Stop

The real strength of this lens is its sharpness with teleconverters. I use this lens regularly with the EF 1.4C TC II and the 2X TC II. Believe it or not I can hand hold the 300/4 IS with a 2X TC II which is the equivelent of a 600/8 because of the Image Stabilization Technology. It makes an awesome Butterfly Lens as well.

Above is an image captured with the Canon 300D, 300/4 IS + 1.4X TC II at f/5.6, 1/1000 sec, ISO 200 +2/3 Stop.

Andrew Robertson , June 24, 2004; 07:31 A.M.

Oystercatcher, 300 f/4L IS + 1.4x II TC, 10D at ISO 800

Bird photography is fun with this lens! It's relatively small, and the built-in hood is great for saving bulk. I don't hesitate to shoot it wide open.

Oren Barel , June 26, 2004; 01:42 P.M.

The Canon EF 300/4L is my best telephoto lens, it is 480mm equivalent on my 10d, it is sharp and fast.

You can see the attached picture taken from 150 meters !!!


Oren Barel, Israel

Image Attachment: shoval zoom.jpg

Best Action Shots , December 14, 2004; 04:38 P.M.

20D has changed my view for need of fast lenses like f/2.8 since its performance in high ISO like 1600 and 3200 is excellent. I do shoot action sports and 300/4L fits my budget very well. This is one heck of a lens! It's very sharp! I'm very happy with this lens so far.

shiva manjunatha , October 21, 2006; 12:55 A.M.

Here is an image taken with tc1.4x , just noticed recently http://www.flickr.com/photos/shivanayak/274369005/ a slight purple fringe..

Neil Cowley , March 20, 2007; 10:43 P.M.

I've been able to handhold this lens with great success when I've otherwise been out of reach. I rarely shoot anything other than wide open and am consistantly pleased with the results. You can see the IS working in the viewfinder - its really amazing.

Anthony Milton , October 01, 2007; 08:23 A.M.

According to an article on the IS Canon range in October-December 2007 EOS Magazine, page 65 it is stated that the IS of the 300mm F4 IS USM lens is not retained when using an EF extender.

I am puzzled

Toby Thornton , September 19, 2008; 04:16 A.M.

I've pretty much found that I have the 1.4 extender clamped on for most situations when I need distance, probably means I should have bought the 400mm f/5.6L, anyhow here's some samples with the extender on


The IS still functions (well at least clonks) with the extender on, but i'm not sure how effective it actually is.

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