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The EF 8-15mm is special because it effectively delivers four lenses in one: Canon DSLRs with full-frame, APS-H or APS-C cropped-frame sensors all get to enjoy full 180 degree fisheye images which fill the image, while full-frame owners enjoy the additional option of full circular fisheye images. Previously this would have required four different lenses, one of which didn't even exist: until now, there was no option for APS-H bodies to capture a 180 degree fisheye view which filled the image. So if you're a fan of extreme wide-angle coverage and own multiple Canon bodies with different sensors, or are simply wanting a fisheye lens which will cover you for future upgrades, this is going to be a very tempting proposition.
This lens is unashamedly about extremes. It captures an enormous field of view, and like other fisheye lenses, makes no attempt to correct the huge barrel distortion which renders straight lines into bananas. A mere tilt up or down will have a dramatic impact on the geometry of the image if desired, but careful choice or positioning of subjects can actually hide much of the distortion if preferred. Action photographers can dwarf athletes by their surroundings, macro shooters can make their subjects look enormous and those with a scientific or meteorological bent can capture the entire sky right up to the horizon. Meanwhile an enormous depth-of-field ensures a huge range of distances is in sharp focus - and once again that massive 180 degree angle of view is now available to cropped and full-frame bodies with a single lens.
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Canon EF 8-15mm Fisheye optical design
The Canon EF 8-15mm Fisheye is a unique lens in terms of optics with a couple of surprises I'll come to in just a moment. But first a brief mention of the actual optical design which consists of 14 elements in 11 groups, seven diaphragm blades and a constant f4.0 focal ratio throughout its range. Some may be disappointed it doesn't share the f2.8 aperture of the existing EF 15mm fisheye, or the Nikkor 14-24mm zoom, but in use you rarely miss the extra stop.
There's already such a massive depth-of-field even at f4 that shooting at f2.8 wouldn't exactly blur backgrounds, while the coverage is so wide you can easily shoot at slow shutter speeds without needing the extra light. Astro-photographers always appreciate an extra stop, but for those very long fisheye exposures of trailing stars the aperture is normally closed down a little anyway. The bottom line is while brighter is always nice to have it's not missed on the EF 8-15mm Fisheye. Besides equipping it with an extra stop would have made the lens much larger, heavier and more expensive.
There's no Image Stabilisation, which may not come as a surprise - again the ultra wide coverage means you can successfully handhold this lens at relatively low shutter speeds. That said, IS can be a valuable ally when filming video, and I noticed wobbles on some handheld footage which stabilisation could have ironed-out. The temptation with this lens is to get extremely close to your subject, so even though there is a massive field of view behind it, you may still notice surprisingly small movements in the foreground. The bottom line is this lens is not immune to visible wobbles when filming video, so beware.
The next surprise concerns the closest focusing distance: a mere 15cm which compares favourably with the 20cm of the earlier EF 15mm fisheye. Remember both distances are measured from the focal plane rather than the front of the lens, so in reality you can focus on a subject that's about an inch from the front element. This can be pretty hairy in practice as you find yourself getting closer and closer to a subject just to render it into a decent size, before glancing up to find it almost touching that precious front element. You'd also better get used to funny looks from passers-by as you virtually prod your subject with the lens.
The biggest surprise though concerns the coverage. Unless you're familiar with the way fisheye lenses work, you'd naturally assume an 8-15mm zoom would deliver just under a 2x range from wide to really wide. But in reality there's virtually no zoom at all on this lens, at least in the conventional sense. Believe it or not, the actual zoom range of the EF 8-15mm Fisheye on a full-frame body is about 1.03x. So what's going on?
The easiest way to explain this is to first consider its performance on a full-frame body. At the maximum focal length of 15mm, the lens delivers an angle of view measuring 175.5 degrees on the diagonal. Zoom-out just a fraction to the 14mm mark and you'll reach the maximum 180 degree diagonal angle of view. This is as wide as the lens ever gets and is known as a full-frame or diagonal fisheye. You're getting the full 180 degrees on the diagonal, but the rectangular shape of the frame means the edges are cropped, slightly reducing the horizontal and vertical angle of view.
| Canon EF 8-15mm Fisheye coverage on full-frame body | ||||||
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| Canon EF 8-15mm at 15mm | Canon EF 8-15mm at 14mm | Canon EF 8-15mm at 13mm | Canon EF 8-15mm at 12mm | |||
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| Canon EF 8-15mm at 11mm | Canon EF 8-15mm at 10mm | Canon EF 8-15mm at 9mm | Canon EF 8-15mm at 8mm | |||
Canon EF 8-15mm Fisheye coverage on 'full-frame / 35mm' body | ||
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| 8-15mm at 15mm | 8-15mm at 8mm | |
Fit the lens on an APS-H (1.3x crop) or APS-C (1.6x crop) body and you'll initially capture a smaller angle of view than a full-frame body, but at around 12mm on the former and 10mm on the latter, the maximum 180 degree diagonal angle of view is achieved, after which it's just a case of revealing more of the imaging circle and the blackness beyond it. The difference between these cropped sensors and full frame though is you'll never see the entire circle. With the lens set to its shortest 8mm focal length, an APS-H body will show 180 degrees diagonally and horizontally, but the vertical side is cropped a little. On an APS-C body, it's tighter still and you won't quite achieve 180 degrees horizontally, instead just having black corners to the image.
Canon EF 8-15mm Fisheye coverage on APS-C 'cropped-frame' body | ||
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| 8-15mm at 15mm (26mm equivalent) | 8-15mm at 8mm (12.8mm equivalent) | |
Since most people won't want to see the imaging circle unless it's in its entirety, Canon positions markers on the barrel to indicate the maximum coverage on APS-H and APS-C bodies before vignetting begins. There's also a physical limiter for APS-C bodies which prevents you from zooming wider than 10mm, but sadly owners of APS-H bodies will have to keep an eye on the markings alone. It's worth remembering most DSLR viewfinders don't have 100% coverage, so just because you can't see the vignetting creeping into the corners doesn't mean it isn't actually being recorded. Luckily the 10mm limiter keeps APS-C bodies free of vignetting and all APS-H bodies are 1D series with 100% viewfinders; Live View will also show 100% coverage.
You may also be wondering how the coverage on the EF 14mm f2.8L II compares, after all, 14 is wider than 15, right? Well once again be prepared for a surprise as these are quite different optical designs. The EF 14mm f2.8L II may have a 14mm focal length, but it's an ultra-wide lens with relatively minimal distortion. The diagonal coverage on a full-frame body is 114 degrees.
In contrast, set the EF 8-15mm Fisheye to 14mm on a full-frame body and as described earlier, it'll deliver a 180 degree view on the diagonal. That's a considerably bigger field of view than the EF 14mm f2.8L II, and understandably comes with equally considerable distortion. If you like straight lines in your images, this lens is not for you as the barrel distortion transforms anything beyond the very centre of the image into severe curves. You'll need to carefully position subjects in the middle and ensure the horizon crosses the centre to avoid them being rendered into bananas. Even then, anything approaching the edges will be distorted whether you like it or not.
You also have to be very careful with framing a 180 degree angle of view, because if you point the camera straight forwards, it'll capture everything from directly above and below, including your feet. It's easy for your arms to also become visible in the periphery and you often find yourself holding the camera in unusual poses while leaning forward to avoid making an appearance. Point it vertically upwards at 8mm on a full-frame body and you'll record the entire sky with a 360 degree view of the surrounding horizon. It's certainly a unique proposition.
Canon EF 8-15mm Fisheye design, build quality and focusing
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Weighing 540g it feels reassuringly dense, but never heavy. That's only 65g more than the lightweight EF 17-40mm f4L and about 100g less than either the EF 16-35mm f2.8L II or EF 14mm f2.8L II. It is understandably a little larger and heavier than the ageing EF 15mm f2.8 Fisheye prime, which measures 73x62mm and weighs 330g, but again carrying the EF 8-15mm never felt like a burden.
The build quality lives up to the 'L' range with everything feeling tough and well put-together. The relatively short barrel length leaves little room for both a zoom and manual focusing ring, so each is noticeably narrower than those on, say, the EF 16-35mm f2.8L II and EF 17-40mm f4L. That said, both the zoom and manual focusing rings on the EF 8-15mm are perfectly usable, and like other 'L' lenses are both silky smooth in operation.
Sandwiched between the two rings is a focus distance window. It takes about a 90 degree turn of the manual focusing ring to go from one end to the other, and as a USM model it supports full time manual focusing. Autofocus is quiet and swift, taking less than a second to focus throughout the range, although the extreme perspective on the lens means it can sometimes be hard to precisely position an AF point over the desired subject. Then again with an enormous inherent depth-of-field, focusing isn't your biggest issue with this lens.
There's two switches on the barrel, one to choose between Manual Focus and Auto Focus, and the other to set the zoom limit for APS-C cameras. As described earlier, the EF 8-15mm Fisheye begins to vignette at focal lengths below around 10mm on APS-C bodies, so the limiter can be set to prevent you accidentally going beyond this point, thereby avoiding any darkening in the corners.
Canon also provides two guide marks on the barrel to indicate where vignetting will occur on both APS-C and APS-H bodies, so that when you're adjusting the focal length, you'll know where to stop to avoid darkening in the corners; these are labelled 'C' for APS-C and 'H' for APS-H.
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Just staying with the zoom for a moment longer, the front element extends from the barrel by about 2mm at the extremes of the range, dipping back roughly halfway in-between at around 11mm. The focusing is entirely internal.
Moving onto the rear lens mount, the EF 8-15mm Fisheye features a rubber ring for sealing, along with grooves to accommodate slide-in gelatin filters - after all, you won't be attaching any filters to the front of the lens.
Which brings me to the most striking thing about the EF 8-15mm Fisheye lens: its highly curved front element. This stretches across almost the entire front of the lens barrel, with little border around it. Like other fisheye lenses, it's also highly convex, peaking about one cm higher in the middle than the edges. It's an impressive-looking piece of glass, although one which can't help but look highly vulnerable.
To make cleaning easier, Canon has equipped this front element (along with the rearmost one) with a new water-repellent Flourine coating; indeed I believe it's the first Canon lens to use it. You'll certainly want to keep it clean too as any significant marks on the front element will visible in photos or spoil lighting flare elements.
I'm pleased to report the new coating seems to work well. I shot with the EF 8-15mm Fisheye mounted on a 1D Mark IV body during a Slope-style Ski contest and regularly found myself and the equipment sprayed by snow. Thankfully neither the lens nor body flinched and water droplets on the front element either ran-off or were easily wiped-off, leaving a clean, unmarked surface. Similarly after shooting dusty mountain biking, a quick squirt with a blower brush and a gentle wipe-down brought the lens back to looking brand new.
Of course dust and moisture are one thing; scratches are another entirely. Canon supplies the EF 8-15mm Fisheye with a substantial plastic lens cap which clips onto the outer rim of the lens hood. Both are fairly unusual, so I'll spend a little time describing them.
I'll start with the lens hood, a thin petal design, which clips into place and requires a push of a button to turn and release; this is a quick but secure design, which is necessary as you may find yourself taking it on and off fairly frequently. When mounted on a full-frame body, the periphery of the lens hood actually begins to appear in the frame at around 13mm and quickly becomes obtrusive as you zoom further out. As such you'll only really want to use it on a full-frame body at the longest focal lengths. Switch to an APS-C cropped body though and you'll be able to use it throughout the entire range.
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That said, three of us took a lot of photos with this lens under some pretty demanding conditions, snow or dust everywhere, whipping it in and out of bags, and while we were all fairly cautious, the lens still looked brand new at the end of it. You don't really want to put this to the test, but it may be a lot tougher than it looks. Time and anecdotal evidence will tell.
As a quick postscript, it's important to note while the EF 8-15mm Fisheye does have a large and convex front element, it's nowhere in the same league as the Nikkor 14-24mm f2.8 which measures 98mm in diameter, 132mm in length, features a huge built-in lens hood and weighs almost double at 970g.
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