This may be before you were born, but I can recall the excitement that greeted the first practical 24mm lens for 35mm SLRs. It was the Nikon Nikkor 24mm of 1967. It used nine elements and had taken the better part of ten years to compute… by hand. It transformed photojournalism as it could be used at full aperture and its close-focusing performance was surprisingly good thanks to the then very snazzy internal moving groups.
Let’s jump to today. I’m as excited now as I was then about Sony’s brand new 24mm E-Mount lens, the ultra-fast f/1.4 GM. It’s the eighth in Sony’s line of premium G Master lenses so it has a high bar to attain. Its stand-out feature is apparent when you unpack the gem: it is surprisingly small. It sits about half-way between the first Nikon 24mm that weighed only 240g (but was f/2.8) and the current f/1.4 competition (from Nikon, Canon, and Sigma) that weigh 650g or more. The Sony weighs 445g – only two-thirds the weight of the competition – and it’s also about two-thirds their bulk.
Compactness is not just about having less to carry around, but having a less intimidating presence. Look at the filter size. For both the Nikon and Canon lenses it’s 77mm, while the Sony takes a 67mm. 10mm may not seem like much, but it makes a big difference to how intimidating a lens is to a subject.
In addition, short focal length lenses show clearly the benefits of the mirrorless camera. The rear of the 24mm f/1.4 is only about 14mm from the sensor. In SLR designs that distance needs to be at least 44mm. This difference leads not only to more compact lens mechanics, but easier lens computation.
On the Camera
So let’s mount this super-fast wide-angle prime lens on the camera. In combination with an α7 body it is well balanced, and even better so with the battery grip. There’s a wide focusing ring and – glory be! – an aperture ring. This can be switched between click-stopped or clickless (I love using it clickless). You can also turn the ring to set to ‘A’ so you can control the aperture setting from the camera dials or for when you’re working with shutter priority.
We have in our hands a lens offering an angle of view of 84º on the diagonal, and it can focus to only 240mm. Even in the low light of my study, auto-focus is rapid and sure: much better than my other f/1.4 lens, the 50mm. The manual focus action is smooth and even, but I would personally prefer a little more resistance, which would improve the silky feel.
We can expect this lens to deliver clear, sharp images that arise not only from good optical design but also excellent construction. And it does in delightful buckets. At full aperture, it delivers images with a gorgeous signature with that rare combination of wide-angle and shallow depth of field. Be assured that the entire image field is high usable, at all apertures. The best overall aperture is about f/8.
Full Aperture, Full On
What matters is what this lens can do that others can’t. And here this new optic is quite exceptional. For a start, the lens is very sharp and usable from full aperture with very little full aperture flare. Of course the Sony gets sharper with stopping down, but starts a downward trend in contrast from f/11, which is why the minimum aperture is limited to f/16. Close up, the quality is very good too. Distortion, for practical purposes, is not visible, making the lens suitable for architecture.
One aspect of performance that totally floored me is its ability to control flare and ghosting. I found I could not induce internal reflections or ghosting however I pointed the lens into the glaring sun. In fact I stopped trying because I was worried about burning the sensor. It’s possible to cause some flare (veiling glare) but take a look at the shot through leaves into the sun. Amazing!
The other outstanding aspect of the lens is one that was never a concern before, and it’s the quality of the out-of-focus blur. In this optic, the blur quality – or bokeh – is double cream to the first-crop strawberries of its sharpness.
What is Bokeh For?
Everyone seems to be in search of ‘good’ bokeh (i.e. the quality of out-of-focus blur). But have you noticed that discussions on bokeh almost exclusively covers the quality of out-of-focus highlights? The cool thing to have are discs of unsharpness that are circular in shape, smoothly gradated, without onion-like rings. While out-of-focus highlights grab the headlines, quality bokeh is important for something else.
Good bokeh help define texture. Since texture consists of areas that are slightly de-focused as well areas in focus, the quality of that blur contributes to the definition of the texture. The smoother the blur image, the more true and life-like the texture. This is most important with skin tones. In my thinking, that’s why good bokeh is important for portrait lenses. It’s not the highlights, but the out-of-focus skin tones that really benefit from smooth blur.
There is a ‘but’, however. The more you work with out-of-focus effects, the more you have to accept the aberrations that cause coloured fringes. This is because the sensor is picking up the bundles of light spreading out like a rainbow. You usually see this at the edges of the image bundle, but with this lens at full aperture, it occurs closer to the centre. Most of the time you won’t see it, but if you push the contrast at hard edges, it’s evident.
Having the lens for only a few days, and living in Auckland, I couldn’t point it at stars. The promotional text says pains were taken to deal with aberrations that astro photographers don’t like, so that’s something to look forward to. In every department that I experienced – from physical presentation to auto-focus speed to imaging – the 24mm f/1.4 GM is an outstandingly rewarding lens to use. Frankly, it was huge fun.
It’s neither a general-purpose lens nor cheap, so if you’re a landscape photographer who loves extensive depth of field, there’s little point shelling out for (the Sony 24mm f/1.8 is a first-rate lens at about half the price). On the other hand, street and travel photographers or photojournalists who like the wide-angle view will find this a dream lens. You’ll be able to shoot action with auto-focus down to very low light levels yet be confident of top-notch results. And you can work with out-of-focus effects with ease. What’s more, its compactness means that overall it easily out-classes the competing optics. It’s now on my list of ‘must haves’!
About the Author
Tom Ang is a Sony Digital Imaging Ambassador and a leading authority on photography, having written over 40 books on the subject. He has worked as a photographer, picture editor, magazine editor, university lecturer, consultant and international juror. You can learn more about Tom by visiting his website: www.tomang.com