At Photokina in 2012, simultaneously with the announcement of the Sigma 35mm 1.4 lens, Sigma's vision on lens design is presented, which is based on the scope of a lens. Sigma distinguishes between Contemporary, Sports and Art lenses.
The Art Series is designed with an emphasis on the highest optical performance and a "maximum expressive power.” This Sigma 35mm 1.4 review examines the first lens in the Art series, which will further consist of various high end lenses ranging from macro lenses, fast lenses with a fixed focal length up to ultra-wide angle. In announcing the Sigma 35mm 1.4, Sigma emphasizes that the design of this lens limits the longitudinal chromatic aberration to a minimum. That makes us very curious. Because this form of CA, also called color bokeh, occurs especially in fast lenses with an aperture of f/2/8 or greater and is difficult to correct.
Sigma 35 mm 1.4 @ f/1.4
A lens with a 35 mm focal length on a camera with a full frame sensor is a good alternative to a 50 mm standard lens, and the wider field of view of a 35mm lens is very useful in street photography or documentary photography. The high brightness inspires artistic tabletop photography in which you play with the background blur, as in the picture above.
Attention to detail: do you ever doubt when loosening or tightening a lens hood whether you are turning in the right direction? The lens hood of the Sigma 35 mm 1.4 offers a solution by means of text and arrows on the lens hood. Another point that shows an eye for detail is the AF / MF switch on the Sigma 35 mm 1.4. Even without reading glasses, it is easy to see whether the switch is set to AF or MF, thanks to a white patch under the switch.
Sigma has paid great attention to the construction of this lens. The Sigma 35mm 1.4 DG HSM is tested in the factory with a high dissolving Foveon sensor, allowing the smallest production defects to be detected by Sigma before the lens leaves the factory. The lens has a metal mount that is stronger and more wear resistant, enabling the mount to have an even longer life. Several internal parts are made of metal or the new composite material TSC (Thermally Stable Composite), which exhibits strong similarities to metal. Despite the professional execution, the lens is not additionally sealed against water, as you often see in professional lenses.
This lens is (eventually) available with a Sigma, Sony (D), Nikon (D), Pentax or Canon mount.
The Sigma 35 1.4 mm makes use of internal focus, so that the relatively large and heavy front lens does not have to be removed. That not only means that the front lens does not rotate while focusing, but it usually results in a higher AF speed too. According to Sigma, focusing is smoother thanks to an improved algorithm. The Hyper Sonic Motor (HSM) focuses fast and quickly in combination with a Canon 1D X. Manual correction on the focus is possible at any time by turning the focus ring (full-time manual focus). The manual focus ring is nice and wide, and the resistance is just right.
The Sigma 35mm 1.4 is not equipped with built-in image stabilization. Personally, I do not mind much, but it does mean that the resolution of images taken from the hand with a shutter speed of 1/60 second or longer decreases.
In this part, Sigma scores "just fine" on a camera with a full frame sensor. In the evaluation of lenses, we use 1 scale for all systems and on a camera with an APS-C sensor, the score of this lens will be much higher. The degree of vignetting of the Sigma 35mm 1.4 is representative for the vignetting of this type of lenses on a camera with a full frame sensor. At full aperture and after stopping down once, the vignetting is visible if you photograph a smooth exposed subject, such as a blue sky. Nevertheless, after stopping down twice, which is already at f/2.8 due to the high brightness, the vignetting of the Sigma 35 mm 1.4 is completely disappeared.
The Sigma 35 mm 1.4 does well at this component. The distortion of the Sigma 35mm 1.4 is so low that even at the most critical forms of architectural photography, you will find no interference from visible distortion.
For a lens with a 35 mm focal length, the Sigma 35mm 1.4 has a remarkably quiet bokeh. Especially if you are close to the subject and choose aperture 1.4, you get a nice quiet background blur. Once you stop down, the circle of a pointy light source becomes smaller and less round. At aperture 2.8, you start to recognize the corners of the aperture.
Click on the image for a 100% image cropping of the bokeh at aperture 1.4.
With some distant subjects, you notice that a 35mm lens is not optimal for a nice bokeh, as you can see in the example here.
Click on the image for a magnification of this image on the place of the red dot.
Also in this section, Sigma has clearly taken great care of the lens design. Obviously, the lens elements are equipped with Super Multi-Layer Coating, which reduces flare and ghosting in bright backlighting. However, Sigma has probably done more than applying the SMLC. Because this lens shows virtually no flare or ghosting, despite a complex design of 13 lens elements in 11 groups. In practice shots, we have encountered no ghosting and flare. In the studio, even after removing the lens hood, we were still struggling to take a shot in which you can see some visible ghosting.
In terms of resolution, this lens satisfies the dreams of even the most demanding photographer. In our Sigma 35 mm 1.4 review, we have found the highest resolution we ever have measured on a Canon camera. And to think that the test took place on a Canon camera with "just" 18 megapixels, the Canon 1D X. Up to diaphragm 4, the edge and corner resolution remain behind on the high center resolution. Remaining behind is a relative term, because even in the extreme corners we already measured a resolution of more than 1500 lines per picture height starting at full aperture. Not long ago, we tested cameras and lenses that did not even show such results as optimal results at the center. From aperture 5.6, the images are sharp from outer edge to outer edge.
A correction of aberrations is important for good optical performance. To design a precision lens, a correction of aberrations is crucial. There are several types of color aberrations, namely, chromatic magnification errors and axial chromatic aberration. Chromatic magnification errors can be corrected with photo editing software afterwards, but axial chromatic aberration cannot be corrected afterwards. This lens has glass FLD elements ("F" Low Dispersion), which have the properties of Fluorite and glass SLD elements (Special Low Dispersion). Both types of aberration are corrected thanks to an optimum centering. The lens has ultra-high quality over the entire focus range. Thanks to the use of aspherical elements at specific places, astigmatism and image field curvature are also corrected. The result is a superior and best resolution up to the image edge.
To satisfy our pixel peepers, we have further magnified the picture in search of the last remnants of color bokeh. In the image of branches against a bright sky, you can see in the enlargement to 300% scraps of lateral chromatic aberration at the corners. In addition, in the center, you can see the last scraps of longitudinal chromatic aberration.
Click on the image for a 300% enlargement of color bokeh and the correction recipe in Lightroom. Move your mouse over the image below to see how well Sigma has suppressed the color bokeh.
Exclusively for the new product line, Sigma has developed software ("SIGMA Optimization Pro"), with which you can update the lens firmware yourself and adjust parameters such as back focus or front focus. Occasionally it can be useful, because front focus and back focus depend on the combination of individual cameras and lenses.
In the tested combination of the Sigma 35mm f/1.4 and the Canon 1D X, we had no need for a correction of front focus or back focus. The few blurry practice shots were all traced to the wrong targeting of the center AF point (by us). Optimum focus at aperture 1.4 with a lens with such a high resolution requires extra attention and precision of the photographer, if you want to get the highest quality from this amazing combination.
WYSIWYG score: This table shows the performance of this lens if you store the files in the camera as jpg, where you have all available in-camera lens corrections applied. This score gives you for this lens/test camera combination: "What you see is what you get".
Pure RAW score: This table shows the performance of this lens when the file is stored in the camera in RAW format. This score approaches the intrinsic quality of the combination of lens and test camera.
Extremely high image quality
Construction and finishing of very high level
Exceptionally low color bokeh
Very little flare and ghosting
Attractive price / performance ratio
Focus ring is unreachable when the lens hood is in the transport mode
No additional sealing against water
No built-in image stabilization
With the first lens from the Art Series, Sigma actually sets a new standard. You notice in everything in the chain of design, production and quality assurance that perfection is sought. Not only the finishing is of a high level, but also the optical performance is top notch. We were very curious whether Sigma would indeed have succeeded to eliminate the color bokeh / longitudinal chromatic aberration. This is indeed the case. Nevertheless, the resolution, distortion, and absence of lateral chromatic aberration are of a very high standard.
We do not often say that the price / quality ratio is good of a lens of almost 1000 euros, because for less than 1000 euros, many good lenses are for sale. However, the results of our Sigma 35mm 1.4 review were of such a high level that we exceptionally say that this lens has a very attractive price / quality ratio.