In 2010, the acclaimed L-series of Canon’s professional lenses is extended with the Canon 70-300 mm (Canon EF 70-300mm f/4-5.6L IS USM). This is a compact and versatile telephoto zoom lens with a 4.3x telephoto zoom range and a variable brightness of f/4-5.6. In mid-September 2012, we have published a Canon 70-300 L review with a Canon 650D. The crop factor of 1.6 of the Canon 650D APS-C sensor allows you to have a field of view equivalent to a 480 mm lens on a camera with a full frame sensor. In our previous Canon 70-300 mm L review, this lens has performed very well. Many photographers therefore use this lens on a camera with an APS-C sensor.

Nevertheless, because this lens is designed for use on a camera with a full frame sensor, we have also tested this lens with a Canon 5D MK2.

The focal length range of the Canon 70-300 L makes the lens an ideal lens for action photography, nature photography or portrait photography. When you photograph something at close range, you get a small depth of field, which allows you to isolate the subject from the background well. Some photographers will prefer a slightly faster lens, for fast action photography for example. However, if you do not want to compromise on image quality, it will cost you much more than a Canon 70-300 L.

Construction

The Canon 70-300 mm L is solidly built and therefore quite heavy. The lens is additionally protected against splash water and dust. At a focal length of 300 mm, the lens is about one and a half times longer than at a focal length of 70 mm. On the lens are 3 switches: AF/ MF, IS on/ off and IS mode 1/ mode 2. The first image stabilization mode stabilizes in 2 directions, while the second stabilization mode is intended for image stabilization while the camera is pulled along a moving subject.

The lens is protected from weather conditions, allowing photographers to take pictures even under harsh conditions – even in the desert or rainforest. The black rubber ring can be seen clearly in the image here.

{insertgrid ID = 289}Canon’s new fluorine coating makes cleaning the lens easier and prevents stains or streaks. The Canon 70-300 mm IS USM f/4-5.6L comes with a lens hood and lens pouch. If you want to use this lens on a tripod, the purchase of an optional collar C (WII) is recommended.

Autofocus

Because of a ring-type USM AF motor, the autofocus (AF) operates quickly and silently. The AF motor works in combination with the lens CPU and advanced AF algorithms for accurate and reliable focusing. The AF results have also showed a high reproducibility of the autofocus in our review. The Nikon 1 advertising slogan “With me, every photo hits the mark” is also applicable to Canon.

As with all Canon L-series lenses, full time manual focusing is always possible, even if the AF motor is enabled. A minimum focal length of 120 cm is relatively short for a lens with a 300 mm focal length. That also makes this lens suitable for close photographing of, for example, a butterfly.

Image stabilization

Canon’s advanced optical Image Stabilizer (IS) provides photographers with a four-stop IS advantage (according to Canon). As a result, a photographer can use longer shutter speeds than what would be possible with handheld photography without image stabilization. We have not reviewed the image stabilization in combination with the Canon 5D MK3, but in our previous Canon 70-300 L review, we are very excited about the proper image stabilization of this lens.

Vignetting

To our surprise, we have found slightly lower vignetting in the Canon 5D MK2 RAW files compared to the vignetting in jpg files. We do not have an explanation for this. At full aperture, the difference is half a stop and visible to the naked eye. Move your mouse over the Imatest chart or over the image below for a comparison of vignetting in RAW and JPG files.

We have compared our results for RAW files with a site that also measures vignetting in RAW files (Photozone) and our results for JPG files with a site that measures vignetting in jpg files (Lenstip). Our results are consistent with the two other sites.

Like distortion, vignetting can be properly corrected using software such as Canon’s DPP.

Distortion

In our Canon 70-300 L review on a Canon 650D, we have found a low distortion throughout the zoom range. On the Canon 5D MK3, a camera with a full frame sensor, the distortion is bigger of course. With the design of this lens, Canon has probably chosen to keep the distortion as low as possible at a focal length of about 100 mm. At a focal length of 70 mm, there is visible barrel distortion. At a focal length of 200 mm or larger, there is visible pincushion distortion. These are not unusual values ​​for this type of lens. In most applications of a telephoto lens, this distortion is not striking. Nevertheless, if you want to correct distortion with software afterwards, make sure that you do not frame too small.

Bokeh

An eight-blade circular aperture results in a nice round bokeh with the Canon 70-300 mm, which is ideal for portraits. The background looks nice, especially if you take into account the fact that this lens is not so fast with f/4-5.6. On the right, you see a magnification of the bokeh at 70 mm. Yet the slightly faster Canon 70-200 mm IS L f/2.8 is a better choice if you want to have a beautiful bokeh.

Flare

The individual lens elements of the Canon 70-300 mm L lens feature Canon’s Super Spectra coatings to prevent internal reflections and flare. In addition, a lens hood is included for protection against strong backlighting.

Nevertheless, prevention of flare does not seem to be the strongest part of the Canon 70-300 mm L. In the studio, we have encountered ghosting and flare when we photographed right into a bright light source. In practice, radiation is confined to a limited area around the strong light source. The fact that we have encountered flare and ghosting is not so surprising if you consider that this lens exists from 19 elements in 14 groups.

Resolution

The Canon 70-300 mm L performs very well in terms of resolution over the entire zoom range with the Canon 5D MK2. The performances clearly state that this lens is part of the professional L-series. The resolution in the center (blue bars) is higher than in the outer corners (red bars). This difference is only measurable and not visible to the naked eye.

Normally, telephoto zoom lenses show a lower resolution at the longest focal length. The resolution becomes slightly lower with the Canon 70-300 L, but the Canon 70-300 mm L still yields a high resolution at the longest focal length.

Chromatic aberration

Thanks to the application of two UD elements (ultra-low dispersion), the chromatic aberration in Canon 5D MK2 jpg files of the Canon EF 70-300 mm f/4-5.6L IS USM is low at all focal lengths and apertures. Even with a visual assessment of RAW files, we have encountered no visible chromatic aberration. Very good!

Conclusion Canon 70-300 mm L review

Pros

• Uniformly high resolution over the entire focal length range
• Very solid construction; additional protection against splash water and dust
• Built-in image stabilization
• Low chromatic aberration

Cons

• Visible vignetting
• Visible barrel distortion at 70 mm and pincushion distortion over 200 mm
• Sensitive to flare

The Canon 70-300 mm L is, given its optical performance and solid finish, an attractively priced compact telephoto zoom lens. The higher vignetting and distortion that you get, when using this lens, makes the total score of the Canon 70-300 mm L review half a point lower than the final score of our Canon 70-300 mm L review on a Canon 650D. Those who shoot in RAW can easily remove this difference by using the standard lens correction profiles in Canon’s DPP software, Lightroom or Photoshop. In short, this is a lens to use with pleasure for years.