Carl Mrozek /
08.20.2014 10:10 PM
Canon’s EF 28-300 mm USM L IS Lens

There are multiple sets of prime lenses now available for use with DSLRs and large sensor digital cine cameras available in various price ranges. However, the selection of multipurpose “pro zoom” lenses that could be called affordable is somewhat restricted. If you add another criterion—a zoom ratio of more than four or five to one—then that list shrinks to less than a handful. However, there is one EF-mount-only lens that combines an impressive focal range (especially on the telephoto end), but still goes wide enough to serve as a general-purpose lens, especially with a full sensor camera.

As you may have guessed, this optic was designed for use as a still photo lens; however, budget-minded DPs haven’t let that become a deal breaker ever since the DSLR/large sensor revolution revealed a paucity of bona fide “cine zoom” lenses available below the $5K mark. Canon’s EF 28 to 300 mm f-3.5-5.6 USM L IS lens is a notable exception, which is why I had to try it out.

FEATURES
The EF 28-300mm f-3.5 to f-5.6L IS USM lens features an exceptional zoom ratio of nearly 11 to one, making it useful for a broad range of applications including sports, nature, documentaries, TV commercials and general purpose EFP—and even ENG—shooting. Moreover, the lens is equipped with a dual-mode image stabilizer that’s optimized either for moving or static shots.

The EF 28-300 mm USM L IS lens
The EF lens feels heftier than its official 3.7 pounds, thanks partly to all of the L-series Pro glass it contains: 23 elements in 16 groups, including three UD and two aspherical elements for aberration correction and for optimal optical performance throughout its focal range.

The lens also may have the longest zoom ratio of any lens not expressly made for video capture purposes. It’s impressive too in that you can focus down to 2.3 feet throughout the zoom range for eye-popping close-ups.

This large lens is also reasonably light sensitive, opening to f-3.5 at 28 mm and f-5.6 at 300 mm. In video mode, exposure may be adjusted manually or automatically. For maximum exposure control, however, it should be adjusted manually to expose for highlights, shadows or for something in-between.

The lens uses a push-pull zoom mechanism, meaning that the focal length increases as you stretch the barrel forward and decreases as you compress it. A metal collar next to the manual focus ring lets you tighten or loosen the tension on the barrel.

As this is a still photography lens, it really wasn’t designed to zoom smoothly; however, with the tension level set low enough, smooth short zooms are quite doable with just a little practice and patience. (When the tension is set to “max,” the lens becomes a fixed focal length device.)

The lens has several useful features not typically found on cine lenses, including full-time manual autofocus override, an ultrasonic sensor-controlled autofocus motor and a focus range-limiting function. There are two autofocus range options: seven meters to infinity and two-and-a-half meters to infinity. (I found the latter range to be ideal when shooting through glass, fencing or light foliage.)

This lens also has special coatings to minimize ghosting and flare and to resist dust, moisture and even water droplets, making it ideal for outdoor use in less than perfect conditions. The front element can accept a standard 77 mm filter for extra protection.

This lens is fairly user-friendly, particularly for those familiar with Canon’s EF lens series.

Another feature worthy of note is Canon’s Image Stabilization (IS) system. According to the company, when you’re using IS in still photography you can handhold the camera at three f-stops less than when you’re using a non-stabilized lens. For video applications, “level 2”—which is optimized for panning—should be used as the default mode.

IN USE
I tested the 28-300 with two Canon DSLRs: the EOS 60D and the more compact Rebel XTI. With its blond barrel, black rubber adjusting rings and basic design and proportions, the 28-300 unit looked strikingly similar to my own long EF lens, a Canon EF100-400 mm, although it’s a bit heavier in hand.

I relaxed the “tension” on the barrel so that I could zoom in and out as smoothly and quickly as possible. I also wanted to attempt some short zooms with the review lens, even though it wasn’t designed the way most variable focal length lenses are. The key was to keep the tension level low, but set with just enough resistance to moderate the zoom speed. This does require some amount of trial and error. effort.

The really frustrating element here was that I had to keep re-tweaking things, as the tension ring often locked up with the focus ring, thus taking things outside of the “sweet spot.” However, some amount of repeated tweaking usually solved the problem.

Fortunately, the lens’s ultrasonic autofocus function integrates seamlessly with the 60D, including the manual override. If you don’t like what you get with autofocus, then you move things manually. The autofocus isn’t flawless, particularly in shadows where depth of field is shallow. This sometimes triggered a “hunting” behavior and resulted in variable soft focus, so it’s nice to be able to revert to manual mode.

Ergonomically, the autofocus and image stabilizer switches are both recessed and “sticky,” so they can’t be inadvertently changed while you’re shooting. The adjustments are also clustered close to the camera for easy “blind access” while shooting. However, as the switches are all identical to the touch and “sticky,” users should be cautioned that switching while shooting is ill advised.

A great example of the utility of using both the autofovus feature and the manual override occurred while I was shooting deer in woodland at dusk. The Canon Series III 1.4X extender that I was using reduced the maximum aperture to f-8 in the 200 to 300 mm range. Hence, the depth of field experienced was very shallow in the fading light, with the autofocus sometimes keying on trees and branches rather than on the deer.

On the other hand, the I found that the extender made it much easier to nearly fill the frame with deer, with only immediately adjacent foliage affecting the AF. I quickly overrode this by manually tweaking the focus.

It’s worth noting that the 60D, and Rebel XTi both lack full-frame sensors and this results in a 1.6X crop factor. This means that even less of the softer, outer perimeter of the lens is used when shooting, as most of the action is captured in the lens’ sharpest center core. This allowed me to use the best parts of the high quality L-series optical elements for maximum sharpness.

Even when the lens was operated with its iris wide open at f-5.6, the image corners remained quite sharp through most of the high end of the focal range. Edge sharpness was even better in partial sunlight, enabling me to stop down one or two more steps.

As may be expected, the results in bright sunlight were better (even with extenders), when maxed out between 200 and 300 mm. The key thing was always being in focus, even with kinetic subjects such as wildlife, by manually tweaking as needed.

I didn’t notice any vignetting issues, although I really wasn’t shooting the kinds of subjects that typically trigger it, so I can’t confirm that this may be a potential issue under some circumstances.

I also didn’t encounter any problems with the stabilization system which I kept set mostly on level “2” for vibration-free panning and tilting. According to Canon, it’s important to keep the system on, even when shooting from a tripod, as this lens senses when a tripod is being used with the camera. Keeping the stabilization system activated when using the camera/lens package on a tripod is also recommended to take full advantage of the secondary IS mode, thereby reducing the chance for loss of image sharpness from shutter activation, camera handling and wind-induced vibrations.

I also briefly tested the 28-300 lens on Canon’s XL H1 1/3-inch CCD camera, using a mounting adaptor which probably doubled the device’s 1.6X (APS-C) DSLR crop factor. Whatever the de facto crop, I was able to fill the frame with the image of a stationary snowy owl at least 120-feet away.

I experienced perfect sharpness all around the frame, along with decent depth of field and very good overall color rendition in full sunlight conditions. The images also intercut seamlessly with the other footage I’d shot with the Canon 20X video lens plus a 1.5X front-mounting tele-extender.

SUMMARY
By itself, the EF 28-300 mm is a versatile, well-designed rugged lens with excellent optics and internal stabilization for use with DSLRs and large sensor digital cine cameras, and also with some broadcast cameras via adaptors. With its broad focal range, the lens can fill many production niches, especially in sports and wildlife applications, thanks to features such as manual override autofocus, two-stage internal stabilization and dual-range autofocus.

Despite some warnings to the contrary, I found that this lens can be used with Canon series III tele-extenders to take its nearly 11X zoom to an impressive 600 mm, although it’s not recommend for work at the full 600 mm zoomed-out focal length. Combined with an additional crop factor of 1.6X, this yields—with most nonfull frame sensors—a lens that’s equivalent to nearly a 1000 mm focal length on a 35mm SLR camera, making it ideal for many applications where telephoto power is key to capturing those special shots.

Carl Mrozek operates Eagle Eye Media, and specializes in wildlife and outdoor subjects. His work regularly appears on the Discovery Channel, The Weather Channel, CBS, PBS and other networks. Contact him at eagleye11@gmail.com.

FAST FACTS
APPLICATION

Television production with DSLRs and large sensor digital cine cameras.
KEY FEATURES
Broad focal, selectable focus range, manual autofocus override, dual-stage internal stabilization, removable tripod collar, rugged construction
PRICE
$2,689
CONTACT
Canon
800-820-6610
www.usa.canon.com



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