Canon EF 24mm f/2.8
Lab Test Results
(From Canon lens literature) 24mm lenses are the entry into ultra-wide angle photography and this lens is the ideal starting point. It is extremely sharp and offers superior correction of linear distortion, and its ƒ/2.8 aperture makes it easy to use with slow, fine-grain films or in low light.
July 21, 2008
by Andrew Alexander
The Canon 24mm ƒ/2.8 is a small wide-angle lens, first introduced by Canon in 1988. It uses a design of 10 lens elements in separate groups; however, the use of rear lens cell focusing improves AF performance by not requiring the movement of many elements.
The 24mm ƒ/2.8 was released long before the advent of digital SLR camera bodies, designed to fit a full-size 36 x 24mm film frame. Thus, it will have no problems mounting on either Canon full- or sub-frame camera bodies. On a Canon digital body, it will have an effective field of view of either 39mm (1.6x) or 31mm (1.3x).
The 24mm ƒ/2.8 is still actively manufactured by Canon, takes 58mm filters, and it available from dealers for around $300.
Canon's come a long way since 1988, as the sharpness profile for the 24mm ƒ/2.8 will attest. Wide-open performance exhibits quite a bit of corner softness, on both sub- and full-frame camera bodies. The fact that our review sample is slightly de-centered doesn't help matters.
Wide-open at ƒ/2.8, there is a small sweet spot of sharpness which would ideally be image-center, but in the case of the copy we reviewed, locates around the bottom-right of the frame. Corner softness is quite significant, from 3 to almost 7 blur units depending on the corner you look at. Image sharpness improves dramatically closing down by just one stop: at ƒ/4, more than half of the image is sharp (1-1.5 blur units) with very slight corner softness (2-3 blur units). This situation improves again at ƒ/5.6, where the image is essentially sharp across the frame, and you see the best results for sharpness at this setting. Diffraction limiting begins to affect image quality at ƒ/8, but even at ƒ/11 average sharpness doesn't exceed 2 blur units. At ƒ/16 and ƒ/22, we see a generalized softness across the image, not exceeding 4 blur units in the worst case.
|Sharpness, ƒ/2.8 on EOS-5D|
On the full-frame 5D, we get a true picture of the nature of this lens, warts and all: corner softness is literally off the charts when shooting wide open at ƒ/2.8. However, it's worth noting that central sharpness is very good (even if it's hard to make out in the graphs), with sharpness in the 1-2 blur unit range. We view a lens producing absolute sharpness as a desirable, as you can't remove softness in post, but you can add it. If you wanted to isolate a central subject by making it sharp and having soft corners, then this would be the lens (and the setting) for you.
Similarly to the 24mm performance on the 20D, set to ƒ/4, the corner softness decreases substantially, but it isn't until ƒ/8 that it drops off completely. Central image sharpness is still best at ƒ/5.6.
The lens does show some chromatic aberration, but only as it is stopped down progressively. Wide open at ƒ/2.8, we see around 3/100ths of a percent of frame height of CA generally, and around 7/100ths in the corners. The ''worst'' showing of CA is with the lens set to ƒ/22; on our sub-frame 20D, average (central) CA performance is around 5/100ths of a percent of frame height, but maximum (corner) CA performance tops 10/100ths.
The larger pixels of the full-frame 5D mitigate the CA performance results. Stopped-down (ƒ/22) performance is much better, not exceeding 6/100ths CA, otherwise, performance is about on par with the sub-frame 20D.
Corner shading for the 24mm ƒ/2.8 when mounted on the Canon 20D isn't an issue: the corners are a half-stop darker than the center when set to ƒ/2.8, but at any other aperture, corner shading is insignificant.
|Upper left corner, ƒ/2.8 on EOS-5D|
On the full-frame 5D however, it's another story. Corner shading is a factor at any aperture setting, and it's particularly significant when shot wide open at ƒ/2.8. At this setting, the corners are 1 2/3 EV darker than the center - it's actually off the chart on our vignetting graph. This corner shading improves at ƒ/4 - ''only'' a full-stop darker - and pretty much evens at at ƒ/5.6 and above, where the corners are essentially a half-stop darker than the center.
Distortion is fixed on the 24mm ƒ/2.8, and it's basically the same on either the sub-frame 20D or the full-frame 5D: -0.5% barrel distortion in the corners, and around -0.3% barrel distortion in the center. Fortunately, this distortion isn't complicated, and can be easily corrected in image post-processing software.
The Canon EF 24mm ƒ/2.8 pre-dates USM technology, and uses the older AFD motor. Consequently it's a little slower to focus than modern lenses, and makes more noise in the process. However, it's still relatively snappy. Overriding autofocus is only possible by entering manual focus mode - a selector switch on the side of the lens.
With a minimum close-focusing range of 25 cm (10 inches) and a magnification ratio of 0.16x, there are better choices for macro work than the 24mm ƒ/2.8.
Build Quality and Handling
The Canon 24mm ƒ/2.8 is a small and light lens, weighing just 270 gm (9.5 oz). It's easily tossed in a spare pocket or that unused section of the camera bag, so one can always have a wide-angle prime at their disposal. Build quality is high, with a metal body mount (but plastic filter threads). A windowed distance scale provides distance information in feet and meters, and the only switch selects between autofocus and manual focusing modes.
The focus ring isn't exceptionally wide (1/4'') or tactile - it uses a simple plastic texture - but there is enough travel (90 degrees, around a quarter-turn) on the ring for accurate manual focusing. The ring travels very smoothly, which I'm given to understand isn't always the case for pre-USM lenses.
Canon had already abandoned aperture rings by the time this lens came along, so your body has to have the capability to select apertures to work properly with this lens. Six straight aperture blades provide hexagonal-shaped bokeh. The front filter ring doesn't rotate during focus, making working with polarizing filters much easier; the filter size is 58mm.
An optional petal-shaped lens hood is available (EW-60II), that ads 1.25 inches to the overall length.
Canon EF 24mm ƒ/1.4L USM ~$1,100
We haven't tested this lens, but if ƒ/2.8 isn't fast enough for you, Canon has the solution which offers two additional stops of light-gathering ability. The ƒ/1.4 is a USM L-glass lens, meaning it should do just about everything faster and better than the ƒ/2.8 version, but cost more than three times more.
Canon EF 24-70mm ƒ/2.8L USM ~$1,200
It's usually an unfair comparison to match a zoom to a prime lens, but in this case, the 24-70mm L-glass bests the 24mm ƒ/2.8 prime in almost every category at 24mm; it's sharper, shows less CA, and has much less corner shading. It's also a USM lens, but is four times the price and is significantly heavier and bulkier.
Canon EF 16-35mm ƒ/2.8L II USM ~$1,500
Again, this lens is in quite the different category than the 24mm prime, but it is indeed an option if price is no object. Sharpness and CA performance are much better, distortion is about the same as is corner shading. A USM lens, it will focus must faster and give the added benefit of a wide zoom range.
Sigma 24mm ƒ/1.8 EX DG Aspherical Macro ~$340
We haven't tested this lens, but the Sigma provides an additional stop (well, +1.3EV) of light-gathering ability. It's a fair bit heavier, but has much better numbers for macro work: 0.37x magnification.
Compared to modern equivalents, the 24mm ƒ/2.8 seems to be due for an update. We've had some interesting discussions about the nature of focus and field curvature in wide-angle lenses, and it could be that if you arranged your subjects to match the curvature of the lens, everything would be sharp. That doesn't regularly happen in real-life, though: people tend to compose along flat planes, and that's conveniently how our tests measure sharpness. In this regard, shot wide-open, the 24mm ƒ/2.8 shows high levels of corner softness (extremely high, on full-frame bodies), which may or may not be a desirable effect. CA performance is good, corner shading is good (except on full-frame, where it's objectionable) and distortion is about what you'd expect for a wide-angle lens.
On balance, however, it's not overly expensive, and if you want wide-angle on a budget, it's one of your only options.
Thanks to Mike for pointing out the Canon EF 16-35mm as another alternative.
The VFA target should give you a good idea of sharpness in the center and corners, as well as some idea of the extent of barrel or pincushion distortion and chromatic aberration, while the Still Life subject may help in judging contrast and color. We shoot both images using the default JPEG settings and manual white balance of our test bodies, so the images should be quite consistent from lens to lens.
As appropriate, we shoot these with both full-frame and sub-frame bodies, at a range of focal lengths, and at both maximum aperture and ƒ/8. For the ''VFA'' target (the viewfinder accuracy target from Imaging Resource), we also provide sample crops from the center and upper-left corner of each shot, so you can quickly get a sense of relative sharpness, without having to download and inspect the full-res images. To avoid space limitations with the layout of our review pages, indexes to the test shots launch in separate windows.
Canon EF 24mm f/2.8
Canon EF 24mm f/2.8 User Reviews
7 out of 10 points and recommended by Ashley_Pomeroy (6 reviews)Sharp in the very middle at all apertures; sharp almost to the corners at f/8; small; light; good colour, contrastFeels redundant - you really have to want it; overpriced; physically old-fashioned
I wanted a small, wide autofocus prime lens for my full-frame Canon 5D. I already have a superb 24mm lens - a tiny Olympus 24mm f/2.8 that I use with an OM-EOS adapter - but I find myself running out of patience with manual stop-down and zone focus. I want something that I can use on the fly, on the hoof, in changing conditions, one-handed, so that the camera is an extension of my will instead of an apparatus that I have to hold and operate.reviewed January 17th, 2010
Canon's prime range appears to be almost uniformly great above 50mm; at 50mm it is variable but generally very solid; wider than 50mm it is variable. The 35/f2 seemed like a good choice but is apparently soft in the corners, the 20/f2.8 comes across as a dog, the two 28s don't appeal to me. The L primes including the 24mm f/1.4 are no doubt superb, but if I had £1,000 to spend on a lens I wouldn't spend it on a lens, I'd spend it on a fortnight's holiday to Italy. The fast zooms that encompass the 24mm focal length are also large and expensive, and the 24-80mm I used to own wasn't great at 24mm. The Tamron 24-135mm I also used to own was good at 24mm but bulky.
Which leaves the 24mm f/2.8. It's is one of Canon's oldest primes, and is a fairly obscure lens. The only sustained piece of writing about it on the internet is a piece at Prime Junta, written by "psulonen", who is one of the reviewers below. The lens is obscure because its full-frame focal length overlaps with a bunch of popular zooms, including the 17-40mm, and so most photographers already have something that is as wide or wider. If you have the 24-70/f2.8 it doesn't even have speed on its side.
Physically the lens is plastic, slightly more girthsome than I expected. The autofocus goes vzzz but the focus travel is so small that moving from infinity to close-up takes a split-second. The tiny manual focus ring rotates freely when in autofocus mode.
On my 5D it's sharp in the middle at all apertures, with roughly the outer 10% of the corners being mushy at f/2.8. At f/8 roughly the outer 5% at the corners are mushy (the edges are fine, and to be fair this corner softness tends to be lost in grass, soil etc at the bottom of the frame). There's a certain, mild amount of red/cyan fringing, which is fixed with a setting of -20 red/cyan in ACR. At 24mm and f/2.8 it's hard to throw the background out of focus, but to my eye the background blur looks a bit "busy", with lots of well-defined circles rather than a smooth paste.
One thing I have noticed is that, at closer focus ranges, the lens is less wide than my Olympus 24mm f/2.8. Based on the samples I have shot, the Olympus lens is sharper across more of the frame, but of course it's more fiddly to use. This leaves me in a quandry, though. If I go on holiday it would be silly to pack both; it would be irritating to waste time fiddly with a manual focus, manual stop-down lens; it would be silly to not capture foreign scenery with the best optical quality I can afford. These conflicting requirements gnaw at my mental well-being.
Colour and contrast are subjective things. To my eye it seems to be a colourful, contrasty lens, rather than a washed-out yellow mess as per the Sigma 15-30mm I was glad to get rid of. My copy at least seems to have a slightly purple bias.
I don't have a formal test set-up, and of course I'm biased in favour of a lens I paid for with my own pocket. I'm not likely to go on the internet and tell the world that I bought a lemon. Nonetheless SLRGear's test results seem unusually pessimistic. The review at Photozone.de suggests that the lens has pronounced field curvature, which might explain why it seems to perform so poorly at f/2.8.
On a crop-sensor camera it would be a decent walkabout 31-38mm depending on whether you have a 1.3x or 1.6x camera. I have an old Kodak DCS 560, which is a Canon-mount digital SLR with a 1.3x crop sensor, and in that context it's a handy all-purpose lens that is sharp across the frame one stop down. The problem with this is that almost all crop-sensor zooms are sharp across the frame one stop down, and a lot of them have image stabilisation as well.
Would I recommend it? If you have a crop-sensor camera it doesn't make a lot of sense although it is generally sharp across the frame. If you have a 24-70mm f/2.8 it's almost pointless. If you're going abroad and you need to pack light and small - this is me - it makes a certain amount of sense. Cropping off the outer 5% improves the image quality greatly although it's still not quite as good as my Olympus 24mm, which admittedly is a vintage manual focus lens that only works with an OM-EOS adapter. 24mm is noticeably wide but relatively mundane by modern standards; it's not eye-popping. At the retail price of about £350 it's overpriced for what it is. It seems to be the best mid-range wide Canon prime although it's a shame that it's not objectively the best mid-range wide prime.
7 out of 10 points and recommended by photonut (5 reviews)small, sharp, fun to use
I've owned this lens for a little over a year now and I was shocked when I first saw the official review pop up here. They must have hit a bad copy as it does not match my own experience at all. The off-center blur plot is a bit of a giveaway too.reviewed November 15th, 2008 (purchased for $280)
Anyway, I bought this lens before a trip in the summer of 2007 without being sure it would be useful. I was quite wrong: I ended up taking most of my pictures with it and it stayed on my camera most of the time. It's light and is a good walkaround focal length on a 1.6x body. The picture quality is simply great! When I got back I had a few pictures printed at 8x12... and this lens at f/4 was so much sharper than my 17-85 at f/8. I simply couldn't believe it. I ended up selling the 17-85 the next year.
The build quality is quite good, focus is fast enough (for what it matters at that focal length anyway), balance is great on a 30D. It's sad that as a prime it's only f/2.8 but to be honest I shoot it at f/4 or f/5.6 most of the time and have not missed the extra stop that much. When I want narrow DOF I just use my 35 or 50.
8 out of 10 points and recommended by tipsy1956 (1 reviews)Small, convenient to carry, light, relatively cheaponly f2.8, no hood comes with it
My copy on a crop certainly doesn't reflect the tests by slrgear.reviewed November 8th, 2008 (purchased for $220)
Certainly it is decently good at f2.8 ( with corners slightly soft ) but at f4, it is improved greatly and you can't ask anything better at f5.6. Perhaps slrgear has got a bad copy? I actually bought this lens twice, I sold it after I got the tamron 17-50 f2.8 which I wasn't so happy with, and finally I bought it a second time after I sold the tamron 17-50.
I use it as a go about lens, with a 50 f1.8 II as the longer lens. The combination is cheap, light, and convenient. Only disadvantages is no wide angle since 24 mm is 38mm cropped which is a mild wide angle. I certainly wish it is a f2.0 which would make a great standard lens.
8 out of 10 points and recommended by ckhorne (8 reviews)
This lens is very good for walk around indoors, where the subject is tight, and there's plenty of casual portrait shots. I really enjoy the ability to take pictures using natural light (to maintain the lighting/mood), and this lens lets me do that. Otherwise, I'm relying on my f/4 IS lens, which can't quite seem to bridge the gap.reviewed January 14th, 2007
This is a good lens for the price - the build quality is ok, but usable - it doesn't feel cheap. It's a useful lens to keep in your bag for those times when a lower f stop is required.
7 out of 10 points and recommended by markenoch (2 reviews)Good sharpness, small and lightweightedFlare problems
I had this lens for about a month. Bought it used. I used it as a walkaround lens, since with the 1.6x multiplier, it is has about the same fov as a 35 mm lens for film. A range I used much in the film days. Construction is good but not great. The focus wheel is a little flimsy and overall it feels somewhat cheap. Autofocus is fast but noisy. It makes a buzzing like sound as it focuses. Sharpness is good even wide open on a 6 megapixel camera. Didn't notice much vignetting either. But didn't look for it. My copy had severe flare problems when doing nightphotography. But then again I bought it used, so it could have been a former owner maintance problem - I suspect there was something wrong with the coating. That made this lens useless for me. But if you wan't a small, lightweight and cheap lens and like the 35 mm fov, then you should give this a closer look.reviewed December 3rd, 2006 (purchased for $150)
7 out of 10 points and recommended by jeffn (6 reviews)Excellent optical quality; lack of distortionAverage build quality; not a lot of "snap"
Very good glass: center is sharp wide open. Stopped down to f5.6 and you are sharp corner to corner. Distortion free.reviewed November 25th, 2006 (purchased for $300)
This is my first choice for on-tripod, panoramic compositions.
It's small, light & handy.
8 out of 10 points and recommended by psulonen (6 reviews)Very compact, nice enough optics, solid all-around performerNot very bright for a prime, not significantly better than many zooms
(Comments based on tests and experience on the EOS-5D.)reviewed October 23rd, 2005
One Canon's "pocket primes," the 24/2.8 often falls through the cracks: not too many people seem to own one. I think the reason is the large variety of 24-something zooms, most of which are not much darker nor much pricier than the 24/2.8, and some of which are very good. And there's its big brother, the big, pricey, and two stops brighter 24/1.4L.
Taken on its own terms, the 24/2.8 is a very nifty little lens, packing a quite an optical wallop for the small size. It's excellent wide-open, sharp in the center, with moderate light fall-off and corner softening. The corners get steadily better until f/8...f/11 or so, by which time the frame is very very good. It also has remarkably little distortion or CA.
The lens is highly resistant to veiling, and moderately resistant to flare spots even in extreme circumstances like night cityscapes. The six-blade iris does give its signature to highlights, which you may or may not like.
In use, it's a simple, reliable performer. The AF is on the noisy side, but quite quick; it's internal focusing too with all that implies. No fancy widgets like USM or such, build is solid but nothing special.
I can highly recommend this lens for anyone looking for... well, this kind of lens. That is, a very compact 24 mm prime, for whatever reason. If you're just looking for a good 24 mm, you won't really gain much by picking this over, say, the 24-85/3.5-4.5 USM -- perhaps a bit of sharpness wide-open and a half-stop or so of brightness.
In a nutshell, while being a very nice lens in its own right and having no glaring problems, it is bound to have something of a limited appeal simply for being what it is. But if you like what it is, go ahead and get one -- I don't think you'll be disappointed. And do get the rather nice petal hood Canon offers for it as well; it really makes a lot of difference.