REVIEWS - Canon EF 70-300mm F4-5.6 L IS USM

OVERVIEW

On our past vacations the Canon 70-200mm F4 L IS USM has been the de-facto telephoto zoom lens. The 70-200L F4 L IS is an outstanding lens, producing sharp images, nice contrast and rich colors. Though, the F4 aperture is a bit slow, and producing highly blurred bokeh is tricky. With the Canon 70-300mm F4-5.6 L IS USM I wanted Canon to maintain the 70-200mm F4 performance level and just add more reach. The Canon 70-300L is more than just a tweak of the 70-200mm F4 variants - the 70-300L has 3 aspherical elements, a floating element system and circular aperture blades.

BUILD QUALITY

The first thing I noticed was the 70-300L’s girth. For some reason I had it stuck in my head that the lens was about the same as the Canon 24-105mm F4 L IS. The 70-300L is about 1 inch longer, so similar, but longer. Compared to the Canon 70-200mm F2.8 L IS II, the 70-300L is about an inch shorter and almost half the weight. The 70-300L is a tad heavy as a travel lens, but compared to the 70-200L F2.8 L IS II, the 70-300L's weight reduction is a big, big improvement. The Canon 70-200mm F4 L IS USM is the lightest of the bunch, but its lack of reach always left me wanting for more during vacations.

The lens barrel construction is a mix of metal and durable plastic - presumably some type of polycarbonate. The barrel appears to be mostly metal and the focus ring sections are plastic. The lens feel solid with no wobble or play in its construction. The lens barrel is finished with Canon’s off-white paint with a slightly dimpled texture. In my experience the paint holds up well and resists scratches and marks. Canon uses white paint to reduce heat absorption when used in sunlight.

The Canon 70-300L is weather sealed provided it is mounted on weather sealed camera body and a front filter is used. During a catamaran trip along Kauai’s Na’Pali coast, the lens and Canon 1Ds3 took several direct waves as we sailed through 5 to 10 foot swells. Both camera and lens were dripping wet. Camera and lens kept working without any problems. Another time along the Honoapilani Highway in Maui (the North Shore), winds were gusting 40-50 MPH and kicking up sand and little bits of lava rock. No dust or debris found their way into the camera or lens. But the camera bag had a nice red dusting and literally spoonfuls of sand had accumulated in the pockets, crevices and compartments - and that was just in a 20-30 minute time period.

The Canon box has a long list of feature icons, including include full-time manual focus, USM focus motors, internal rear-focus design and Image Stabilization. Internal rear focusing provides several key benefits. First, the lens remains a constant size when focusing. The front element does not move or rotate, which is good when using polarizer and graduated filters (67mm front filter thread). Rear focus designs generally provide faster auto-focus performance. The ring-type ultrasonic motor provides smooth, noise-free auto-focus (almost silent).

HANDLING

I feel Canon decided to make a tele zoom lens partner for the Canon 24-105mm F4 L IS. The 70-300L is similar size, so it is not overwhelming like the 70-200mm F2.8 lenses. The Canon 70-300L is a very hand-holdable lens. Canon’s newest image stabilization (IS) systems achieve around a 4-stop improvement (reduction) in camera shake. I have shot the Canon 70-300L at 300mm and 1/10 shutter speeds with great results. I have used the lens on a tripod for long exposures as well, using the 1Ds Mark III’s tripod mount without any issues. IS must be turned off if using a tripod (learned this lesson in Seattle).

At times I get blurry shots with the Canon 70-300L and I think it is because I am trying to shoot before the Image Stabilization has settled. Image Stabilization needs a couple seconds to spool up to speed. I have had the same experience with the Canon 24-105L, 70-200L F2.8 IS II, 100-400L and 70-200L F4 IS. It is just poor technique on my part. I know better, but forget...

Canon’s new hoods with the dimpled finish are a wonderful change. They resist rub marks and scratches much better than smooth finished hoods. The 70-300L’s lens hood is Texas sized, so when the lens is extended to 300mm and the hood is attached, it is not a discrete set-up. That said, the hood seems to work well enough. I have not noticed any veiling, ghosting or unwanted flare.

PERFORMANCE

Technically, the Canon 70-200mm F4 L IS USM is a bit more exotic in its element composition than the Canon 70-300mm F4-5.6 L IS USM. The 70-200mm F4 L IS combines 1 artificial fluorite element with 2 UD (Ultra-low Dispersion) elements to help achieve images free of secondary spectrum aberrations. The 70-200mm F4 L IS’ aperture diaphragm is circular, to help create very natural out-of-focus background highlights. The 70-300mm F4-5.6 L IS has much of the same DNA. But surprisingly it has one LESS element than the 70-200mm F4 L IS. Sadly, the 70-300L also lost the artificial fluorite element.

The Canon 70-300mm F4-5.6 L IS USM has a floating lens group. A floating element or lens group improves a lens’ sharpness over the entire focus range. Lenses without a floating element system may be sharp at the near or tele end, but not as sharp at the opposite end. A floating element system resolves this trade-off. The lens’ minimum focus distance is about 4 feet, which is helpful when trying to amplify the bokeh.

The Canon 70-300L delivers pleasing images with rich colors, balanced contrast, good resolution and sharpness. When looking at the 70-300mm F4-5.6 L IS pictures and thinking of past results from the 70-200mm F4 L IS and 70-200mm F2.8 L IS Mark II, the 70-300L seems a bit softer in comparison, but that observation is more towards the 300mm end - which neither of the 70-200’s can do with out tele-converter. Some other observations:

• The central region tends to be sharp with good resolution, but edges can be weak, more so at the 300mm side. Overall, sharpness and resolution feel “greater” than a Canon 24-105L.
• Barrel and pincushion distortion are noticeable. Perhaps this is par for a 70-300L lens, but I do not recall the 100-400L’s distortion being as noticeable. I routinely correct barrel and pincushion distortion in Phase One's C1.
• The image stabilization (IS) is excellent. Canon’s latest IS generations are simply amazing - shooting 300mm handheld with shutter speeds in the 1/10 to 1/40 range is an incredible accomplishment.
• Auto focus has been dependable both in single-shot and servo mode on the Canon 1Ds Mark III. Focus speeds feel the same as the 70-200mm F4 L IS.
• The 70-300L’s aperture speeds are on the slow side, so the bokeh does not compete the Canon 135L or 85L.
• Chromatic aberrations have been a non-issue, thanks in part to Phase One C1's chromatic aberration corrections.
• Since the 70-300L’s aperture is on the slow side, the viewfinder is also dim. A dim viewfinder makes manual focus challenging (for me at least); I tend to stick with auto-focus.

If I had to sum up the 70-300L’s performance in a single sentence - it is sharper than the consumer options, but not quite as good the recent 70-200mm L’s.

CONCLUSION

The Canon 70-300mm F4-5.6 L IS USM is about a big focal range in a compact body. With the 70-300mm F4-5.6L IS and 24-105mm F4 L IS in hand, the pair easily addresses 95% of my vacation needs. I have a wealth of other gear and a good portion goes on the trips along with the Canon gear. After each trip I always wonder why I bothered with all the other gear. I cannot find a single thing to bitch about - except maybe price. But it is pretty hard to complain about price when the product works like it should and does a good job.