Sigma’s evolutionary approach to lens design has already resulted in improvements in quality and performance with each new model – price is no longer the only reason to opt for Sigma’s optics, and in the case of the Macro and OS models has not been for some time. Yet Photokina’s announcement of the new Global vision for Sigma made it clear that it was felt that the products could perform to even higher levels and be design leaders.

It’s easy to dress up optics in a new and contemporary design – during the ’80s and ’90s Sigma’s lenses underwent several cosmetic changes to reflect the styling of cameras and materials – but the 35mm introduces a distinct and new style clearly different, and some may say more upmarket, than many of the alternatives.
The Sigma 35mm f/1.4 DG HSM lens – the first in the new series of lenses which can be reprogrammed and fine tuned through a bayonet-mount attached USB interface – is being hailed as the best lens of its type ever made by reviewers and experts worldwide.
 

 
The new system of setting up every single production lens using an MTF optical bench based on the Foveon sensor appears to have paid off with dividends for Sigma. The optical performance of the 35mm f/1.4 is close to theoretical limits, with a small amount of simple barrel distortion that is easily corrected, and only a trace of chromatic fringe eliminated perfectly by today’s software.
 

Above:At f/5.6 the Sigma proved beautifully sharp and flare free from this New Year’s Day sunset in Scotland.
Below: 100% detail of the sunset shot at f/5.6. Resolution is at the camera’s limit at this aperture.

 
Longitudinal chromatic error is so well controlled that it is possible to take narrow focus zone shots of difficult targets, like black lettering on a newspaper, without showing any of the usual magenta-green shifts which can colour the blurred areas in front of and behind the sharp detail.
 

Above: Outdoors at night, full f/1.4 aperture gets the windscreen in focus but the degree of defocusing in the rest of the view is acceptable.
As long as part of the shot which matters is sharp, you can work wide open.
Below: Wide open indoors, close-ups only have a few mm depth of field. One eye sharp, ears sharp, the other eye a bit soft, nose completely fuzzy!

 
The bokeh of the lens, wide open, is very smooth with a perfect gradual progression from pin-sharp to massive defocusing, and no trace of wiry of double-edged artefacts on the way. Even when stopped down, the lens has a clean bokeh characteristic; it’s a little busier by f/8 than at wider setting from f/1.4 to f/4, the range where it has the most pleasing differential focus.
 

 

At f/2 the image is very sharp where focused but there was not enough depth of field for this deep deli scene.

 

There’s enough light gathering power at f/2.8 to allow ISO 100 for this helter skelter.
The bottom part of the image was dodged by a total of around 3 stops, mostly in the shadow
tones, to show the people – the original just shows black.

 
Contrast is very high, and we tested the lens in all kinds of against the light situations with the sun in the frame and just out, many positions from centre to edge, without inducing any flare patches at all. The coating is Sigma’s new very hard, water and dirt resistant multilayer technology.
 

Above: At f/5.6 the image is not only sharp, most outdoor scenes have enough depth of field to be sharp from near distance to far.

 
In keeping with this, the lens though not waterproof is finely engineered using a high proportion of metal components where needed, with the usual plastic (as found in all good lenses for the last 40 years) to improve weight and handling while also reducing issues with lubricants, thermal expansion and tolerances. The use of a gloss anodised metal sleeve next to the camera is a stylish touch. The whole lens simply feels like class, and as with the optics, the photographic press and web gurus all agree this marks a new era for Sigma. Sigma has always challenged the big brand names optically, producing lenses they could not design at a price to fit in with existing models. Now Sigma would seem to be challenging them mechanically and cosmetically.  

 
We tested the lens in midwinter, with festive lights everywhere, and of course this lets you see what kind of odd shapes and flares are thrown up at the edges and corners by a super fast lens used wide open. The surprise is that if the point light source is in focus, it’s so clean it matches the central performance. There is no visible sign of spherical aberration, coma or astigmatism – the things which a point source reveals best. There’s some curvature of field, to be expected with a semi-wide angle design at f/1.4.
 

Above: A hand-held 1/40th wide open at f/1.4.
The lens is perfectly sharp but care had to be taken to stop it focusing on the trees and putting the abbey out of focus.
Below: 100% detail of the abbey shot at f/1.4 – the Canon 6D has done well at ISO 6400 to produce such a clean image.

Put this stellar performance together with a very crisp neutral colour transmission (balanced, we suspect, by Sigma’s newly installed advanced coating system) and quiet fast HSM focus motor, and for a penny under £800 retail you’ve got a working lens which many professionals are going to order without hesitation. This is a lens we can expect to see in short supply.
 

Below: The Sigma 35mm f/1.4 and hood, fitted to a Canon 6D body.
Canon lenses don’t come with lens hoods, or cases, so when comparing prices you should
always look up the required lens hood – really a necessity with a lens of this type.