Canon EF 24mm f/1.4L II USM

Introduction

Canon EF 14mm f/1.4L II USM was first announced at Photokina 2008 as a replacement for the namesake first generation 24mm f/1.4L prime. The lens compliments a pretty comprehensive range of Canon's ultra wide and wide angle lenses, including another 24mm prime, the ailing Canon EF 24mm f/2.8. Priced at US$1,700 (as of January 2009), the lens is quite expensive by all standards and comes at a premium compared to the previous version of this wide angle prime.

The optical construction of the lens consists of 13 elements in 10 groups in floating design, including 2 Ultra -low Dispersion (UD) elements, which are designed specifically to reduce the amount of chromatic aberration and 2 aspherical lens elements, which improve peripheral image quality. Canon EF 24mm f/1.4L II USM is the first lens in Canon's lineup to sport a newly designed Sub Wavelength Coating (SWC), which despite its weird naming convention should benefit the image quality the lens produces. How much better, compared to the previous 'generation' of coating? Remains to be seen. The lens is by no means small or light in the world of wide angle primes, thanks partly to the pretty large glass elements used in lens as well as all the electronics, including auto-focusing system built in into the lens. The lens weighs 650g (22.3oz) and measures 86.9 x 93.5in (3.4 x 3.7in). This makes the second version of the 24mm f/1.4L slightly heavier and bulkier then the first generation prime.

The build quality of the lens is superb - the barrel is made of hardened plastic, the focus ring is fully rubberized and is pretty smooth. The lens is weather sealed against dust and water particles and the overall build is pretty sturdy, with no wobbling inside or out. Like all modern EF/EF-S lenses, Canon EF 14mm f/1.4L II USM incorporates a fully electronic aperture - there is no dedicated aperture ring and all aperture settings are configured directly from the camera. The lens incorporates a USM type auto-focusing system, although manual focusing is still possible using the dedicated focusing ring. An AF/MF switch located on the side of the barrel controls the focusing mode of the lens. The lens focuses down to 77mm (3in) - that is one of the closest focusing distances in a non-macro lens! The minimum aperture is f/22 and the lens accepts 77mm screw-in type

 

Image

 

The factory box includes Canon EF 24mm f/1.4L II USM lens, front and rear caps, EW-83K lens hood, LZ1319 soft lens case, registration and warranty card. The lens was designed for traditional full frame cameras, so when used on APS-C type bodies with 1.6x crop factor, the field of view of the lens will resemble that of a 38mm prime - not as wide, but still interesting enough for wide-angle photography. Within the scope of this review, the lens was tested on a full frame Canon 5D and APS-C type Canon Digital Rebel XTi bodies.

 

Summary
Lens Composition 13 elements in 10 groups
Angular Field 84 degrees
Minimum Focus 77mm/3in
Focusing Action AF/MF, USM
f-stop Scale f/1.4-f/22, camera-controlled
Filter Size 77mm
Lens Hood EW-83K (included)
Weight 650g/22.9oz
Dimensions 86.9x93.5mmmm/3.4x3.7"
Lens Case LZ1319 (included)

 

Field Tests

Canon EF 24mm f/1.4L II USM is an EF class lens - as such its handling is quite similar to that of any other Canon EF and EF-S lens out there. AF speed is quite decent - the lens moves in into focus without major problems, although as is typical of most auto-focusing systems, the lens would occasionally hunt in low light conditions. Most modern Canon non-macro lenses have a pretty short focusing path, which makes them not very well suited for manual focusing. Canon EF 24mm f/1.4L II USM is not really an exception to this rule, but it is slightly better then most other Canon primes - the focusing ring rotates for about 100 degrees when going from the infinity to the minimum focusing distance. There is also a DOF scale with markings at f/4, f/11 and f/22, which could help you preset the lens to speed up manual focusing. The lens is pretty bulky - if you are using the lens with its hood attached on a camera with a built-in flash, keep in mind that the lens hood blocks some light from the flash, creating a visibly noticeable shadow at the bottom of the image frame.

The lens showed pretty good overall performance in the field. Images remained consistently sharp in the center on both APS-C as well as full frame cameras, although there seemed to be a slight degradation in quality around borders on a full frame body at wider apertures. You can notice from the shots in the sample image gallery below that the quality at wider aperture, between f/1.4 and f/4, are slightly softer then in the center, especially at f/1.4. This is not very surprising though for a wide angle prime, and in many cases would not pose a major problem to most photographers who can use some form of sharpening in post-processing stage.

 

ISO 400, 1/250, f/1.4, 24mm (Canon 5D)
ISO 400, 1/250, f/1.4, 24mm (Canon 5D)

 

The lens produced well rounded out of focus highlight when shot at wide open aperture. The highlights often carried harshly defined outlines, which is common to lenses with over-correction for spherical aberration. There was no sign of double-edging around back/fore-ground OOF objects and contrast transitions were pretty smooth, helping improve isolation of the in-focus subjects.

 

ISO 100, 1/8000, f/1.4, 24mm (Canon 5D)
ISO 100, 1/8000, f/1.4, 24mm (Canon 5D)
ISO 100, 1/250, f/8, 24mm (Canon 5D)
ISO 100, 1/250, f/8, 24mm (Canon 5D)

 

Remember the whole hoopla about Sub Wavelength Coating naming? Well, turns out that setting aside a rather awkward naming, the new coating actually does improve handling of flare. The two shots above demonstrate probably one of the worst possible scenarios with a strong direct light source positioned right within the picture frame. Contrast levels in these shots are obviously drastically condensed, which is not that surprising. Aside from that however, behavior is quite decent - absent are ghosting, striping, rainbowing etc., although you can notice some color fringing in the shadow of the flower in the lower right corner of the picture.

 

Vignetting @ f/1.4 - full frame vs APS-C
Vignetting @ f/1.4 - full frame vs APS-C

 

The lens showed pretty noticeable vignetting at its widest aperture setting when used on a full frame camera. This is not  really that surprising, considering that a rare f/1.4 lens would not vignette with wide open aperture. As you stop down the lens, vignetting levels are reduced and by f/4 light fall-off is pretty minimal. What is more surprising, however, is that on an APS-C camera the lens showed a pretty minimal amount of vignetting, even at f/1.4. By f/2 pretty much all traces of vignetting were gone.

You can notice a minor degree of color fringing, with traces of both axial as well as sagittal chromatic aberration seen in the cropped image below (around the flower pot in the center), as well as in the shot of a street performer in the sample image gallery. Aside from this, rather very mild artifact, color reproduction was quite good, with color palette remaining pretty neutral and images carrying good amount of contrast and saturation. One of the most typical artifacts in wide angle lenses is distortion (typically barrel distortion for wide angles), and this is where the lens delivers the biggest surprise - Canon EF 24mm f/1.4L II USM shows practically no distortion at all. Naturally, 24mm is not the widest possible rectilinear focal length available on the market (Canon, Nikon, Tamron and others have even wider primes and zooms), but the sheer fact that there is no need to deal with distortion in postprocessing should be quite appealing to many users.

 

ISO 100, 1/8000, f/1.4, 24mm (100% crop)
ISO 100, 1/8000, f/1.4, 24mm (100% crop)


 

Lab Tests

Please note that MTF50 results for APS-C and Full-Frame cameras as well as cameras from different manufacturers are not cross-comparable despite the same normalized [0:1] range used to report results for all types of cameras.

Canon APS-C: Canon EF 24mm f/1.4L II USM showcased a very good overall performance on an APS-C type body. The lens does show excellent results in the center across the entire aperture range. Border image quality is quite solid as well, even excellent pretty much throughout the tested aperture range. Once exception though: at f/1.4 border image quality does show a little bit of softness as can be seen from the MTF chart, but the good news is that it is certainly not a disastrous drop-off in quality so typical to many fast wide angles. Still, results are pretty evenly distributed across the frame from f/2.8 through f/8, where the lens is capable of delivering outstanding 19in and decent 24in prints. Conclusion? Very solid performance for this wide angle. Double impressive considering pretty solid performance even at the ultra fast aperture settings.

 

MTF50 (Line Width/Inch on the Print) @ 24mm
MTF50 (Line Width/Inch on the Print) @ 24mm

 

Normalized raw MTF50 @ 24mm
Normalized raw MTF50 @ 24mm

 

CA on an APS-C body was pretty minimal on the center, approaching ~0.6px at f/1.4 and slowly dropping to ~0.2px by f/11. CA around borders was slightly higher, but still manageable - CA around borders at f/1.4 was ~0.85px and dropped to ~0.45px by f/11.

 

Chromatic Aberration (APS-C) @ 24mm
Chromatic Aberration (APS-C) @ 24mm

 

Here are 100% crops, taken with a full frame Canon 5D, comparing image borders at f/1.4 and f/8.

 

Image borders @ 14mm (100% crop): f/1.4 vs f/8
Image borders @ 14mm (100% crop): f/1.4 vs f/8

 

Canon FF: Unfortunately, Canon EF 24mm f/1.4L II USM did give up a little bit of ground (in terms of resolutio) when tested on a full frame body. Center image resolution is still top notch right from f/1.4 all the way through f/11. However, border image quality suffers at wider apertures - at f/1.4 quality is rather mediocre. Borders continue to improve with stopped down apertures - at f/2 is still average, but by f/2.8 resolution finally 'kicks into the gear' and reaches pretty respectable level. Things only improve further, with the lens delivering most balanced results around f/8. Conclusion? The lens disappoints a little bit when it comes down to border performance at wider apertures, but outside of this tricky f/1.4-f/2 range, performance is quite solid.

 

Normalized raw MTF50 @ 24mm
Normalized raw MTF50 @ 24mm

 

Distortion, or actually the lack of it, was the biggest surprise about this lens. To be precise, the distortion test did register barrel distortion, however at ~0.29% it should not cause problems to majority of users.

 

Distortion (FF) @ 24mm
Distortion (FF) @ 24mm

 

Chromatic aberration on a full frame Canon 5D was very well under control across the frame. Center CA did not exceed ~0.4px, while border CA hovered ~0.5px throughout the aperture range. Nothing to stress about.

 

Chromatic Aberration (FF) @ 24mm
Chromatic Aberration (FF) @ 24mm

 

Here are 100% crops, taken with a full frame Canon 5D, comparing image borders at f/1.4 and f/8.

 

Image borders @ 14mm (100% crop): f/1.4 vs f/8
Image borders @ 14mm (100% crop): f/1.4 vs f/8

Alternatives

Canon offers a pretty wide range of wide angle primes, including obviously the first generation Canon EF 24mm f/1.4L USM (which as of January of 2009 seems to have been discontinued), as well as a slower Canon EF 24mm f/2.8 (which by now badly needs a redesign). Interestingly, when it comes down to resolution, the second generation 24mm prime is not that much different from the first generation one. As can be seen from the charts below, there is a slight deviation here and there, but overall pretty similar performance results (it is worth noting though that the EF 24mm f/1.4L II USM shows a noticeably better performance on an APS-C camera, specifically around borders at wider apertures).

 

Canon EF 24mm f/1.4L USM vs Canon EF 24mm f/1.4L II USM - Center (Canon 5D)
Canon EF 24mm f/1.4L USM vs Canon EF 24mm f/1.4L II USM - Center (Canon 5D)
Canon EF 24mm f/1.4L USM vs Canon EF 24mm f/1.4L II USM - Borders (Canon 5D)
Canon EF 24mm f/1.4L USM vs Canon EF 24mm f/1.4L II USM - Borders (Canon 5D)

 

Two other very interesting lenses that you should consider are Canon EF 14mm f/2.8L II USM and Canon EF 35mm f/1.4L USM. The 14mm prime is an especially interesting lens, since it's currently the widest rectlinear prime available in Canon's EF mount. Oh, and then there's also the top notch performance, which is one of the best in the class. There are obviously other wide angle primes out there, notably a whole slew from Sigma, however, if you really want to find a good quality wide angle prime, you should look at alternative mount lenses. This obviously assumes you are willing to tinker a little bit with you camera system and use a manual focus prime. And if you do, then a whole new world of possibilities will open up for you. Among the alternative primes worth considering are Contax branded Carl Zeiss Distagon T* 21mm f/2.8, Carl Zeiss Distagon T* 28mm f/2 (keep in mind though that this lens might not clear the mirror of your full frame camera), Carl Zeiss Distagon T* 28mm f/2.8, Carl Zeiss Distagon T* 35mm f/1.4 and their modern alternatives in Nikon F mount - Carl Zeiss Distagon T* 28mm f/2 ZF and Carl Zeiss Distagon T* 35mm f/2 ZF, as well as Leica R type Elmarit-R 28mm f/2.8 and Summicron-R 35mm f/2.

 

Recommendation

The recommendation for Canon EF 24mm f/1.4L II USM should mirror that of its predecessor - if you liked the resolving capabilities of the previous generation lens, you would certainly like the performance capabilities of the revised one. The lens shows pretty good overall image quality, with somewhat softer results around borders at f/1.4 and f/2 - not that unusual for ultra fast wide angles. But, where the new lens differs against the old one is in handling of various artifacts - color fringing, distortion, flare. Vignetting on full frame cameras is obviously not that good, but it is doubtful much can be done here. The question, however is whether these additional enhancements are worth the extra US$600 you have to pay over the original EF 24mm f/1.4L USM. Maybe, maybe not...