Canon EF 24-70 f/4 L IS USM Lens Review

Introduction

An interesting lens, this latest addition to the Canon general purpose zoom lens line-up. In this class, the buyer used to have the option of getting the EF 24-70 f2.8 Mark 2 lens, or the EF 24-105 f4 L IS USM, a firm favourite for many Canon users, including me. Now there is also this EF 24-70 f4 L IS USM lens, and what makes the situation interesting is the pricing, it slots in between the 24-70 f2.8 and the 24-105 f4 L lens.

Which is slightly confusing; why pay more for a shorter focal length lens, offering the same maximum f4 aperture throughout the zoom range, similar build quality as can be had with the rival 24-105 f4 L lens? There must be some feature that makes this lens stand out from the competition that justifies the extra price tag. And there just might be!

But before we get to that, just some basics on the lens to put it all into perspective.

Specifications
Zoom range: 24mm to 70mm
F-stop range: f4 to f22
Angle of view: 34° to 84°
Filter thread: 77mm
Lens construction: 15 elements in 12 groups including 2 UHD glass elements
Minimum focussing distance: 0.38m (normal mode), 0.2m (macro mode)
IS: Hybrid type, 4 stop (normal mode) 2.5 stop (macro mode)
Focus motor: ring-type USM with full manual override
Focus method: Internal, front element does not rotate during focus
Zoom method: Rotary type with extending lens barrel
Weight: 600g
Accessories: front and rear lens caps, soft pouch, scalloped lens hood.

Analysing the basic specifications yields no real surprises, except for the minimum focus distance data; 38cm in normal mode, and 20 cm in macro mode. Which to the knowledgeable reader and even the enthusiastic user will immediately register as being somewhat closer focussing than most zoom lenses which offer a “macro” function. Further delving into the specifications also show us a maximum magnification of 0.7 X, which is better than the 0.33 or so usually found on zoom lenses with a macro function. (I call them pseudo macro lenses because to me it’s not a true macro function, but more like a close-up function. Macro is 1 X, ie life-size, or better.) But having the close-up capability offered by these pseudo macro lenses is very handy, and now the user can more than double the perceived magnification and get really close to true macro by using this lens. But it comes at a price, on the pocket and the usability.

In the hand
The lens is light and compact enough to be used as a general purpose lens. Physical size, dimensions and bulk are very similar to the EF 24-105 f4 L IS lens, right down to the 77mm filter thread size. The zoom ring was tight but smooth and really easy to use, similar to my personal 24-105 f4 L lens when it was new. The zoom ring is closest to the camera, the manual focus ring closest to the front element. Both have a knurled rubber type ring which affords a really nice grip.

The familiar AF/MF switch is located on the left hand side of the lens, and just below that the IS switch. The Macro switch is on the right hand side and is operated by zooming to 70 mm focal length and sliding the switch to the Macro setting. This effectively locks the lens in the 70mm setting and allows the lens to focus closer than normal, virtually halving the minimum focus distance. It also then allows the zoom ring to use the 70mm Macro zoom setting marked in orange on the zoom scale which basically changes the close –focus standoff distance.

Performance
As is to be expected this lens offers very good optical performance at all apertures throughout the zoom range and does not need to be stopped down from wide open to achieve better results. There is some barrel distortion between 24 and about 29 mm, but not really different as exhibited by other lenses in this class. Sharpness and colour are good, as one would expect from an L-series lens, and will certainly handle most landscaping and portraiture requirements thrown at it, as the candid quick grab shot of my daughter shows. I will probably be in the hot water for this, so don’t tell her!! Using the f4 maximum aperture still provides good depth of field control to blur the background effectively.

In general use the lens shows the capability to deliver crisp detail and true colours as is evident from the Hibiscus flower

Auto focus is quick and accurate, even in low light conditions. I had the opportunity to test the lens in conjunction with the new EOS 7D MkII at a classic motorsport event. Moving in close to the track on the inside of a sharpish left hand turn the cars were whizzing by me with a meter to spare, the concrete safety wall between me and the track. This means I was able to get really close to the action and still remain safe. Whilst there it started to cloud over and a light shower came down, turning the track into a damp strip and providing lots of sliding action from the cars. The shot of the two cars, a VW Polo Classic and a VW Golf, yielded a three shot burst with all three frames sharply focussed, good performance for such close to camera action and faster moving subjects.

^{Canon EOS 1D MkIV, Canon EF 24-70 f4 L IS USM @ 70mm, f4, 1/200, ISO 800}

^{Canon EOS 7D MkII, Canon EF 24-70 f4 L IS USM @ 70mm, 1/100,f11, ISO 400}

^{Canon EOS 7D MkII, Canon EF 24-70 f4 L IS USM @ 30mm, 1/400, f9, ISO400}

Using the lens in the macro mode does offer better macro capabilities than most pseudo macro lenses, and approaches the results from true macro lenses. One thing that the user has to keep in mind is the very short working distance at maximum magnification where the use of an on-board flash will cast a shadow across the subject, formed by the lens hood. I minimised this effect by using my hot-shoe mounted Canon EX 430 MkII flash with a bounce card fitted, and also removed the lens hood. One still has to be careful and monitor the position of the front element in relation to the subject at all times as it is easy to loose perception through the viewfinder and press the front element against the subject whilst trying to obtain focus, or brush against leaves etc. The results from this macro test were promising; the user has to bring his part and learn to use the lens within its limitations, but it is well worth while in the end. Definitely the best macro performance from any of these zoom lenses with a “macro”function I have ever experienced. And this could well be the factor that makes this lens worth the extra cash needed.

^{Canon EOS 7D MkII, Canon EF 24-70 f4 L IS USM @ 70mm Macro, 1/160, f11, ISO400}

Conclusion
An impressive general purpose lens with a better than most macro function, good overall performance, a good option to consider for the user wanting an all-in-one lens in the standard zoom range.
Many thanks to Canon SA for arranging and making available the test lens.