A Non-comparison Field Test: Two 70–300mm f/4–5.6 lenses for full-frame and APS-C Format DSLRs

Canon’s Top-of-the-Line 70–300mm f/4–5.6L
Canon’s new EF 70–300mm f/4–5.6L IS USM is the company’s latest, most advanced offering in this flexible long-telephoto-zoom range. It’s clearly aimed at pros and serious enthusiasts who demand the utmost in image quality, rugged, weatherproof construction, and first rate AF and IS (image stabilization) performance, and who are prepared to pay a premium price (street price: $1599). The lens is beautifully finished in Canon’s signature light gray enamel, and its zoom ring operates with silky precision. The lens is understandably on the heavy side at 2.31 pounds, but it balances extremely well on both full-frame and APS-C-sensor Canon DSLRs, delivering a spectacular 112–480mm equivalent focal length range with the latter. Considering its range and aperture, it’s reasonably compact at 3.5 inches in diameter and 5.6 inches in length. It also focuses down to 3.9 feet, giving a maximum magnification ratio of 0.21, or 1/5 life-size—commendable for a lens of this type. It accepts 67mm filters.

Everything about this lens is optimized for handheld shooting and it will obviously appeal to Canon shooters specializing in nature, wildlife, sports and other genres requiring a combination of reach and speed. What makes it particularly impressive in these applications is its lightning fast, ultra-precise autofocus, and Canon’s latest enhanced version of image stabilization that delivers on its claims, providing four-stop anti-shake advantage when shooting handheld at slow shutter speeds and/or long focal lengths. It also delivers on its promise of capturing images of exceptional sharpness, contrast and detail across the field at all focal lengths and apertures, and happily this extends to its near-macro close focusing range.

We did not really have a chance to fully test its rugged, dust and water-resistant construction, but we did shoot a few dozen frames with the unprotected lens in heavy rain and snow without experiencing any problems whatsoever. We found that it works splendidly on the full-frame Canon EOS 5D Mark II, and was even more impressive on the APS-C-format Canon EOS 7D, which we used to capture some exciting motorcycle images at or near the long end, where it gets out to nearly 500mm equivalent.

The feel, heft and ergonomics of this lens are truly outstanding and manual focusing, crucial for any sports or nature shooter, is extraordinarily smooth and precise. Those accustomed to zooming while shooting may find that the placement of the zoom ring close to the front of the barrel may not be ideal, but if you zoom with your fingertips the ring itself is wide enough to allow you to support the lens with your left hand near the middle of the barrel for better mass centralization. Ultimately, image quality is the motivation for acquiring this lens, and here is where this advanced new 19-element, 14-group design with two UD-glass elements really earns its “L” (which, by the way, stands for “luxury” but really denotes pro performance).

Based on our extensive hands-on experience you can expect superior color rendition, excellent contrast, exquisite sharpness and excellent resistance to flare even under adverse conditions. That, along with superb build quality, AF speed and precision, and IS performance, is what makes the Canon EF 70-300mm f/4-5.6L IS USM, a sound investment for any pro or advanced user.

Tamron’s Innovative 70–300mm f/4–5.6 Di VC USD
The new Tamron SP 70–300mm Di VC USD long telephoto zoom works with full-frame and APS-C-format DSLRs, providing an exciting 112–480mm effective range with the latter. This attractive, well balanced lens incorporates two key technical innovations designed to enhance its real-word performance. The first is an upgraded version of Tamron’s exclusive VC (vibration compensation) image-stabilization system that counteracts the effects of camera shake in three planes and is now claimed to provide a four-stop advantage when shooting handheld. The second is USD (Ultrasonic Silent Drive), an ingenious proprietary AF motor designed to enhance auto-focusing speed, responsiveness and overall AF accuracy. Based on newly developed motor technology and software, it employs a piezoelectric ceramic element to generate two high-frequency ultrasonic vibrations on the motor’s stator ring. This in turn causes the adjacent metallic rotor to rotate by means of deflective traveling waves when voltage of a specific frequency is applied.

The new lens carries Tamron’s SP (superior performance) designation, and the 17-element, 12-group design includes one LD (low dispersion) and one XLD (extra-low dispersion) element aimed at achieving superior correction for chromatic and magnification aberration, both particularly important at long telephoto focal lengths and at close focusing distances. Despite its technical sophistication and fairly wide f/4–5.6 aperture range, the 70–300mm is reasonably compact, with a diameter of 3.2 inches and minimum length of 5.9 inches, and it’s remarkably lightweight at only 1.69 pounds. Its minimum focusing distance of 4.9 feet gives a maximum magnification ratio of 1:4 (f=300mm at 1.5 meters), a useful near-macro close-focusing range. The lens is nicely finished in black and its very wide textured zoom ring is perfectly positioned for handheld use and turns with a smooth action. The lens takes 62mm filters and no tripod mount is furnished.

In our field tests on a Nikon D700 and D7000, we found that this lens delivers excellent overall imaging performance that certainly justifies its SP designation, and that the built-in VC image-stabilization system performs as claimed, delivering up to a four stop maximum advantage in handheld shooting. AF action is very swift and precise except in very low light where the combination of a moderate f/5.6 aperture and the response of the camera’s AF system result in slower and less decisive autofocusing, especially with low contrast subjects. This is not due to any deficiency in the lens, but is a function of camera limitations.

Whenever AF is achieved and camera shake is not a factor, the lens delivers outstanding resolution at all focal lengths and shooting distances, as well as superior freedom from flare when shooting backlit subjects. In our judgment, the overall performance of the 70–300mm Tamron Di VC USD is outstanding, and truly impressive considering its moderate price point (street price: $449). The lens is available in Canon, Nikon, Sony and Pentax mount (the latter two without VC because Sony and Pentax cameras have in-body image stabilization systems).

In conclusion, both these lenses can be highly recommended to anyone seeking a high-quality long telephoto zoom for sports, nature, wildlife, bird, travel, landscape photography or any other use where a relatively wide aperture and long reach is essential. The Canon is unsurpassed in terms of weatherproofing and sheer quality of construction, and it delivers imaging performance of the highest professional caliber. In practical terms, the performance of the Tamron is remarkably close, especially in terms of image quality and image stabilization, and it exhibits a beautiful bokeh in images shot at wide apertures. It is very well made, noticeably lighter in weight, available in a variety of mounts, and is substantially less costly. You definitely won’t go wrong either way, and oddly enough, despite the substantial price differential, each of these high-tech tele-zooms lenses represents an excellent value.

Jason Schneider is best known as a prolific writer and editor on all aspects of photography. He began his career at Modern Photography in the late ‘60s and in 1987 signed on as editor-in-chief of Popular Photography, a position he held for nearly 16 years. Considered an authority on the history of camera design and technology, he has written three books on camera collecting, is an active contributor to leading photo magazines and websites, and is Senior Editor of Photo Industry Reporter, the industry’s authoritative trade magazine.