The Sigma 85mm f/1.4 EX is only the second example of a new breed of fast prime lenses from Sigma, recently joining the 50mm f/1.4 EX to form what now looks like a promising new lineup. We typically expect Sigma lenses to underperform compared to Nikon or Canon lenses with an offer of performance proportional to asking price. On most metrics this new lens is a delightfully solid match however – in fact there is little to fault the optical cell of this 85mm lens – and for most photographers the verdict will come down to secondary qualities of off-brand lenses.
Until recently Sigma avoided many of the most popular lens configurations of prime-lens photographers. Sigma’s first foray into this market, the 50mm EX, derived exceptional wide-open performance from an aspherical design that set it apart from its competitors based on the classic double-gauss design. With the arrival of the 85mm EX lens into the lineup, we can only guess when a fast 35mm lens will come to complete a new triumvirate of high-speed, near-normal EX prime lenses.
My interest in the 85mm EX came from a desire to acquire an indoor sport lens that could double as a versatile auto-focus telephoto. After witnessing a virtual outpour of positive reviews for this Sigma lens I decided to rent a copy from LensRentals for my own evaluations. Sadly the first copy that I received suffered from a hard focus jam; LensRentals immediately sent me another copy of the lens which I used to write this review.
The 85mm EX is longer and larger than most lenses of the same focal length and speed. It is solidly built on the outside, save for a flimsy focus mode switch, and the velvety-rubber skin that Sigma used to finish the lens does much to create a tactile impression of quality. On the D700 the pair is quite a handful, much more so than the 85mm ZF we discussed previously, but the weight is still reasonable for prolonged use thanks to copious use of plastics in the barrel. With smaller cameras the 85mm EX might look disproportionally large though, especially with the hood extension for cropped sensor.
Manual focus is a viable option with this auto-focus lens. The manual focus ring is reasonably damped for an auto-focus lens and travels at a reasonable speed. The best part is that the manual focus ring gave no backlash (play) on the tested copy when changing direction for fine tuning, a common issue with manual focus on auto-focus lenses.
Automatic focus with the 85mm EX on the D700 is usually fast and accurate, and required no micro-adjustments between this lens sample and my camera. The biggest issue I found with auto-focus on this lens is that its low resistance to veiling glare (more on that below) also negatively impacted auto-focus efficacy when the background comprised a light source or very bright object. At one point the problem became significant enough that it forced me to reconfigure my camera to focus only through the AF-ON function, something I never needed to do before.
Nothing moves on the outside of the 85mm EX when focusing. Under continuous servo the tested lens sample squeaked with most changes in direction. I take this as a sign that a focus jam is in this lens sample’s future also.
The 85mm EX is a very sharp lens with low-to-average global contrast and minimal resistance against veiling glare. It is certainly an aggressive competitor to the Nikkor 85mm f/1.4G, compared to which the Sigma trades veiling glare resistance for a much lower price. Comparison to the Zeiss 85mm ZF lens is awkward at best because the Sigma aims for resolution and convenience whereas the Zeiss aims for contrast and richness of color.
At full aperture the 85mm EX resolves a good amount of detail over most of the frame, albeit with low contrast. Resolution at this aperture is surprisingly good when critically focused, and surprisingly even across the frame as well. Stopping down to f/2 improves both micro-contrast and resolution noticeably, up to very good levels in the center of the frame. At f/2.8 and beyond only modest improvements are seen along the axis, while borders and corners continue to improve until f/5.6. At the smaller apertures the Sigma 85mm lens stands with the best lenses on the market.
In my hands the proverbial Achilles’ heel of the 85mm EX was its low image contrast in anything less than luxurious golden light, and below-average (compared to other lenses tested on this site) resistance to veiling glare. It is common for me to maneuver to photograph against bright backgrounds, or even the illuminant for the scene. Under these conditions the 85mm EX had great difficulty focusing, the delivered image contrast was very low, and colors were contaminated by the color of the highest-key image elements (internal reflections not only reduce contrast but transfer color).
Chromatic aberrations, lateral and longitudinal both, were not an issue in my use of this lens.
On the basis of optics alone, Sigma’s 85mm EX is a great lens at a good price. Mechanical issues do much to injure its appeal however, and its weak antireflective coatings don’t do justice to the optical cell it carries. Ultimately it is still the case that one gets what one pays for, but the 85mm EX proves that those trade-offs need not invoke the optical cell.
Would I recommend this lens to other photographers? No. I derived more enjoyment and suffered fewer issues from the 85mm ZF.