The Canon EF 70-300f/4-5.6 L IS lens was introduced in the last part of 2010.  The 70-300mm focal length range is a popular one and Canon already produce a handful of cheaper zoom lenses with similar focal length ranges. The difference is that this 70-300 is the first such L-series offering in this focal length range.  This means that the EF 70-300L IS is a whole level higher in specification and performance than any of the ‘standard’ 70-300mm zooms that Canon already offer.

What Is New?

Well, apart from focal length, this lens shares little in terms of looks with any existing Canon lenses at the time of writing.  It is a fresh design. The lens barrel is constructed of metal, and it benefits from Canons recent design philosophy, which seeks to combine strength and lower weight.

Image Stabilization switches Canon lens

The recessed switches are not likely to be accidentally shifted.

There is a switch panel located close to the lens mount, on the left side of the lens.  It houses switches for AF/MF, and IS On/Off as well as the IS mode.  The switches are of the new, tucked-in type, and require deliberate pressure to move, which is good.   They won’t accidentally get bumped onto a different setting.

Lock switch Canon zoom lens

This switch stops the lens barrel from extending accidentally

There is another switch on the opposite side of the lens barrel, which locks the zoom ring and prevents the front portion of the lens from extending by itself whilst you are carrying the lens. Neither of two copies of the lens that I used were prone to the zoom creeping due to gravity, but it is still nice to have the lock if you need it.

The focus ring turns very smoothly.  The zoom ring is located ahead of the focus ring, and is wider with more prominent ridging than the focus ring.  This is different to the Canon 70-200 lenses, where the zoom ring is closest to the lens mount.  It takes a bit of getting used to if you are accustomed to shooting with the rings the other way around. The zoom ring has no play in it, and operates with a light and positive action.  The inner section of the lens barrel extends during zooming.  At 70mm, it is retracted, and the lens is extremely compact in this configuration.  When retracted, it is short enough to fit into my camera bag standing upright, which leaves lots more room for other things.

Retracted position Canon zoom lens

Canon EF 70-300L in retracted position

Canon Zoom Lens, Extended

Canon EF 70-300L with lens fully extended

At 300mm, the front section is fully extended and increases the size of the lens somewhat. The ET-73B lens hood attaches to the end of the inner section of the barrel by turning and clicking into place quite firmly.  It extends along with the inner section of lens barrel.  This hood is well-made, with Canon’s new scratch-resistant finish on the outside, and anti-reflective flocking on the inside to prevent stray light from entering the lens.  The hood is deep and also provides excellent physical protection for the front element from water, flying debris, dust and bumps.  I am hoping that this lens hood will not become loose and rattly in its attachment, as some of the older Canon lens hoods used to do.  It does not have the locking tab as found on the latest version of the Canon EF 70-200 f/2.8 IS II lens.

The 70-300L has 19 elements in 14 groups, and has two UD (Ultra Low Dispersion) elements that help to minimize or eliminate chromatic aberrations.  Super spectra coatings on some elements also help reduce flare and ghosting.

Front objective Lens Canon 70-300L

Frontal view of EF 70-300L

Both the front and rear elements are coated with fluorine, which helps repel dust, and water or other contaminants. This Canon lens is also fitted with a four-stop image stabilization system.  What the four-stop description actually means is that the new lens stabilization system will give the user a higher probability of getting sharp shots whilst handholding the lens at even slower shutter speeds than earlier Canon IS systems.

Cape Gannet in flight

Canon 1Dmk4, EF 70-300L, 1/8000s at f/5.6. -0.67 Comp. Iso 640


How Well Does It Work?

 The EF 70-300 L is far superior to any of the consumer grade 70-300 lenses that are made by Canon and is totally deserving of its L-series designation. The design is a little unusual in that the outer lens barrel is a lot thicker than the inner barrel that extends when zooming.    This gives the lens a quite different feel to other Canon zooms in this focal length range.  The inner barrel does not rotate when zooming in or out. The lens casing is smooth and cleanly constructed. When retracted the lens has a chunky, business-like look to it.

The lens is no lightweight at 1050g, but that is the cost of the high-quality construction.  It is still lighter than the Canon EF 70-200L f2.8 IS II and the EF 100-400L F/4.5-5.6 IS.

It works perfectly on any Canon dslr, but due to its weight,  seems best suited to the intermediate sized camera bodies like the 60D, 7D and 5D series, as well as the larger 1D series. I have been shooting the EF 70-300L on a Canon 1Dmk4, a Canon 5Dmk3 and a Canon 60D with excellent results.

This lens is weather sealed, which is a big plus.  Even if you don’t use your gear in bad weather, having a weather-sealed lens means that dust and moisture will not easily get inside the lens.  This is a reassuring feature for me as a wildlife photographer. For the weather sealing to be complete, the lens needs a filter to be fitted ahead of the front element, and it should be mounted on a similarly weather-sealed Canon dslr body.  The front element is 67mm in diameter.


Canon zoom lens 5Dmk3 dslr

The EF 70-300L is well-matched to a 5D body

The 70-300L does not come with a tripod ring.  The correct tripod ring for this lens is tripod mount ring C, and it is quite a costly accessory.

The lens feels solid in operation and it is straightforward to use.

The relatively light weight of this lens makes it quite comfortable for me to handhold for long periods, and I found that I became used to the ‘switched’ locations of the zoom ring and focus ring quite quickly.  When I am photographing moving subjects, I like being able to adjust focal length whilst tracking the subject and shooting, and the EF 70-300L made this easy to do.

There is no focus distance limiter, and once you have selected which IS mode to use, you can just get on with shooting. The IS system has two modes.  Mode 1 is for handheld shooting, whilst Mode 2 is for panning or tripod shooting.  The IS unit in the 70-300L is able to detect when it is on a tripod and will function accordingly.  There seem to be differing opinions on the value of IS when shooting from a tripod.  I have found no problem with leaving IS on when I am shooting at fast shutter speeds, in Mode 2.  Having it on makes a difference in how steady the image appears in the viewfinder, and can make shooting easier. However, with some Canon IS lenses, I have found that when I am shooting at very low shutter speeds from a tripod, for example less than 1/20s, that it is best to switch off the IS completely.

Image Quality

This lens takes very good pictures.  Check out sharpness in this 100 % crop from a 16 megapixel file from the Canon 1Dmk4, shot at 300mm and wide open at f/5.6.  This image is cropped to just 1 megapixel for the purpose of showing what detail the lens can resolve.  The crop was sharpened in Adobe Camera Raw and Photoshop, the same way as I sharpen all my images.

Spotted thick-knee, bird, portrait, Canon

Spotted thick-knee. 100% Crop. Canon 1Dmk4, EF 70-300L at 300mm, 1/400sec at f/5.6. Iso 800.

It is sharp enough wide open, whether that be at 70mm and f/4.0 or at 300mm and f/5.6.   Stopping down improves sharpness a little.

There is some vignetting visible on the edges of a full-frame sensor when shooting wide-open at f/4.0 and 70mm focal length.  This lessens significantly by the time the lens is stopped down to f/5.6. At 300mm, and wide open at f/5.6 there is a bit less vignetting, and this also lessens when the lens is stopped down one or two stops.  It will only really be noticeable when photographing subjects against a uniformly bright background, like birds in the sky.  The vignetting is not at an intrusive level for my use, and what there is can easily be removed when processing the image.

When used on camera bodies with smaller sensors, which do not cover the outer edges of the image circle projected from the rear of the lens, there is no vignetting at all. This holds true for those Canon cameras with APS-C sized sensors like the 7D, 60D and 600dD as well as for the Canon 1DMk3 and Canon 1Dmk4 with their APS-H sized sensors. Chromatic aberrations are minimal, particularly around the central part of the image, which is the most important part for a nature photographer like myself.  In fact, the 70-300L has proven to be the best Canon lens I have used so far when shooting leaping marine mammals and the splashes of white water that they throw up.  Some of these splashes end up as small, overexposed circles of white, often with purple edges fringing them.  This purple is a form of chromatic aberration but images I have taken with the EF 70-300L  are the cleanest I have gotten so far. Distortion is also minimal, and not really anything to even mention as it is not field relevant for my requirements. Colour and contrast are good, even in less than ideal light. Overall, if I were to rate the image quality of this lens as it compares to the other current Canon mid-range zooms that I am very familiar with, I would make the ranking as follows:

  1. Canon EF 70-200L f2.8 IS II
  2. Canon EF 70-200L f4 IS
  3. Canon EF 70-300L f4-5.6 IS
  4. Canon EF 100-400L f4.5-5.6

This is a high-quality group of lenses under discussion here, and all four of them are either the best in their class, or close to it. All four of these lenses are more than sharp enough and produce image quality good enough for professional applications and what slight differences exist, may be hard to discern in normal use.

The modest maximum aperture of f/5.6 means that the lens will be used wide-open a lot of the time, especially when used handheld and in less than bright conditions. That maximum aperture of ‘only’ f/5.6 becomes less important if this lens is paired with a camera body that can shoot at higher iso sensitivities without sacrificing too much quality.  Raising the iso sensitivity becomes an option when faster shutter speeds are required. The EF 70-30L f4-5.6 IS surprised me with the speed of its autofocus.  The latest  microcomputers and motors in the lens do a great job of finding focus very quickly, accurately and quietly. Comparing the sharpness of consecutive frames taken in bursts, of flying birds, showed that the EF70-300L was able to provide several very sharp shots in a row. Although it does not always produce quite as many consecutively sharp shots as I get from my fixed telephoto Canon EF300f2.8L IS, or the EF 70-200 f2.8 L IS II, it was still easily good enough to get the job done and superior to the older EF100-400L IS in this regard.

Humpbacked whale breaching, Indian Ocean

Humpback whale. Canon 1Dmk4, EF 70-300L. Focal length 229mm. 1/4000sec at f/5.6. Iso 640

The EF 70-300L f/5.6 IS has become my lens of choice for marine photography. I photograph seabirds, as well as dolphins, and whales each year along the South African coast.  Shooting from a moving, pitching boat on the ocean isn’t easy, but the EF 70-300L can lock focus fast enough on a breaching humpback whale that I am able to capture the whale whilst it is still travelling upwards on its leap. Compared to the 70-200mm focal length that I used previously for this type of photography the EF 70-300L allows me to shoot for longer and spend less time moving the boat. Weather sealing is a big plus on this lens.  The front section of the lens extends during zoom movement, but is sealed where it enters the camera. Minimum focus distance is 1.2m which is good for a lens in this class, and gives decent magnification of small subjects.

Although the lens is not made to accept extenders, I have read reports of it being used with aftermarket manufacturers converters.  I prefer not to use extenders on lenses that are not designed for them.


Canon has quite a number of L-glass choices in the medium telephoto zoom lens.

Compare Sizes Canon Zoom Lenses

Canon EF 100-400L IS, EF 70-300L IS, EF 70-200L f/4 IS, EF 70-200L f/2.8 IS II

Perhaps the Canon lens most similar to the EF 70-300L is the Canon 100-400L f/4.5-5.6 IS.  If you really need that extra 100mm of focal length, then the 100-400L is the one to get.  It is also a little less expensive, especially if you factor in the significant extra cost of the tripod collar which comes standard on the EF 100-400L.  Potential buyers might consider the EF 70-300L for its weather sealing, lighter weight, faster autofocus, slightly better image quality, bigger aperture opening at the short end of the zoom range and a quieter and more effective image stabilization system when choosing between these two versatile lenses.

Canon also make four L-series 70-200mm lenses.  Two of the four have image stabilization, and two don’t.

The pair that are image stabilized are the EF 70-200L f2.8 IS II and the EF 70-200L f4 IS . The EF 70-200Lf2.8 IS II enjoys a wide-open aperture advantage that can be essential for blurring out backgrounds, and shooting in low light.  It should also be more robust, with the lens barrel not changing shape or size when zooming.  This lens also focuses faster, and delivers about the best image quality of any similar focal length Canon zoom.  It is heavier at 1490g though, and costs a lot more.  This lens also works well with a 1.4x converter, although it does begin to get quite heavy and large in that configuration. In comparison the 70-300L is lighter (1050g), cheaper and has that extra 100mm of focal length.

The second IS lens, the Canon EF 70-200L f/4 IS, is very close to the f/2.8 II version when it comes to autofocus speed and image quality.  It is much lighter though, at 760g , and costs a little less than the EF 70-300L.  It enjoys somewhat of a low light advantage on the 70-300L due to the bigger, constant f/4.0 aperture and it doesn’t change shape when zooming.  It is also weather-sealed. The 70-200L f4 IS can also be used with a 1.4x converter.

The  70-200L f/4 (without Image Stabilization) is similar to the stabilized version in size, although it is a fraction lighter (705g) and is not weather-sealed.  It offers image quality quite close to the stabilized version and can be used with a 1.4x converter.  It is the lowest-priced L-series lens of this group of mid-range Canon zooms.

The EF 70-200L f/2.8 (non-stabilized) is an older lens model, and weighs in at 1310g.  It is only partially weather-sealed and offers the same large aperture advantages as the newer 70-200f2.8II IS described above.  It lacks image stabilization but sells for a much lower price than the newer f2.8 lens.  If you have to have the f/2.8 aperture this is the most cost-effective Canon way to do it.  Compared to the EF 70-300L which is the lens in review here, this lens probably holds a slight image quality advantage, as well as the obvious large aperture advantage but it is heavier, and lacks the extra 100mm on the long side of the focal length.  It will work with a 1.4x extender.

Another Canon L series zoom lens in this class is the Canon EF 28-300L f 3/5-f/5.6 IS.  This lens has a significantly wider focal length range than the EF 70-300L.  It too is weather-sealed.  If you only want to carry one lens that can do everything then you might want to consider the EF 28-300L.  In direct comparison to the EF 70-300L though, the EF 28-300L is heaver (1670 g), costs almost twice as much, and cannot quite match the newer lens when it comes to image quality over the focal length ranges that the two lenses do share.

Amongst such an array of L-series offerings from Canon, the EF 70-300L IS does not stand out as having the longest focal length, nor the biggest aperture.  However, it is an extremely versatile lens and that is where much of its strength lies.

Side view, Canon lens EF70-300L

The Canon EF 70-300 f/4-5.6L IS with lens hood ET-73B



The Canon EF 70-300L is a high-quality piece of equipment, and as such, it is a pleasure to use.  The lens has a lot going for it.  Its attributes include fast, accurate autofocus, very good image quality and effective image-stabilization.  Combine all of this with weather-sealing, in a compact and lightweight package, and you have one of those lenses that you just never want to take off your camera.  I enjoyed using this lens so much that after using a loan unit a couple of times, I actually went out and bought one for myself.

Burchells zebra, Equus burchelli, portrait

Burchell’s zebra. Canon 1Dmk4, EF 70-300L. Focal length 229mm. 1/1250sec at f/5.6. Iso 800