Prime Performer: Tamron SP 85mm F/1.8
The Tamron SP 85mm F/1.8 Di VC USD lens produces images that are sharp enough for critical work yet simultaneously smooth. It handles flare and glare well, and as a portrait lens it compresses beautifully. The vibration compensation (VC) feature will give you a perceptible advantage in lower light, keeping you out of higher ISO settings.
With these performance gains, the Tamron SP 85mm F/1.8 is longer, wider, and substantially heavier, takes a 67mm filter, and has a higher price point. The Nikkor equivalent of the SP 85mm F/1.8 Di VC USD sports an electromagnetic diaphragm, found in only a few high-end Nikkors. The Tamron’s street price is $749.
Considering that Canon has not updated the EF 85mm f/1.8 USM since 1992, it isn’t a surprise that the new Tamron outperforms it; the surprise is by how much.
The Tamron SP 85mm F/1.8 focuses quickly and positively, and it’s notably sharp over a wide range of apertures. It handles flare well and has minimal internal ghosting when shooting toward the sun or other light sources. The contrast is excellent with practically no geometric distortion, and VC works as advertised. The lens also feels (and appears to be) substantially built. For video shooters, there's little to no lag when manually focusing.
From f/1.8 to f/2.8 there;s some slight darkening in the corners of the frame, but this is easily corrected in either Adobe Camera Raw 9.6 or Lightroom CC2015.6. I found that when focusing on close subjects below f/5.6, the shapes of far out-of-focus areas in complicated backgrounds started to have a slightly unpleasant visual feel.
In this focal length there are faster lenses like the Canon EF 85 f/1.2 II USM, the AF-S Nikkor 85mm f/1.4G, the Sigma 85mm f/1.4 EX DG HSM, and the Zeiss 85mm Milvus and Otus, but size-wise those lenses are beasts both in size and (except for the only slightly more expensive Sigma) price. Unless you really, really need that extra fraction of a stop speed and are willing to give up image stabilization (and in the case of the Zeiss, autofocus), the combination of overall qualities of the Tamron SP 85mm f/1.8 Di VC USD make it an impressive stand out. (See the image gallery at the end of this article.)
TECHNICAL DETAILS AND REAL-WORLD TESTING
Firmware updates and custom settings
Tamron’s new TAP-in console, enabling firmware updates for specific Tamron lenses (currently the SP 85mm F/1.8, the updated SP 90mm F/2.8 Di Macro 1:1 VC USD, SP 45mm F/1.8 Di VC USD, and SP 35mm F/1.8 Di VC USD) similar to the Sigma USB Dock. It also allows for lens-specific autofocus adjustment settings at up to eight distance segments along with user-determined vibration compensation and focus range limiter settings. The TAP-in sells for $59.
With the Tamron SP 85mm F/1.8 lens on a full-frame camera I can work with my subjects at a conversational distance during a portrait session and still have flattering telephoto compression. The additional weight and size of the 85mm f/1.8 Di VC USD compared to the Canon and Nikkor 85mm f/1.8 lenses is likely due to the more sophisticated and better corrected optics as well as additional elements and mechanics required for vibration compensation.
While there are several full-frame-compatible zoom lenses that cover the short and medium telephoto range and also incorporate some form of light path stabilization, none are faster than f/2.8, and they tend to be even longer, heavier, and more expensive. Photographers gets fatigued schlepping a large-diameter long-barreled lens around, and many subjects are not comfortable having one pointed at them from a relatively short distance.
In portraiture I like to work close, but not so close that I intrude on the subject’s personal space. Whenever possible, I prefer not to use a tripod if the quality of light is suitable. This sort of work requires a short, fast telephoto lenses. Until recently the only lenses up to the task have been the Canon EF 100mm f/2.8L IS Macro IS USM lens and the AF-S VR Micro-Nikkor 105mm f/2.8G IF-ED lens. Both are terrific lenses, but wide open they are a full stop and a third slower than the Tamron SP 85mm F/1.8 and with nearly 15 to 20 percent longer focal length.
I tested the VC function during an impromptu indoor portrait session with a pair of virtuoso mandolin players, Carlo Aonzo of Italy and and Bob Krysz of Atlanta, and also while photographing under stormy skies at the Lady Bird Johnson Wildflower Center in Austin, Texas. Going by the CIPA Standard CIPA DC-011 for measuring image stabilization performance, the lens’ VC feature is good for 3.5 stops. What does that mean in practical English? It's generally accepted that the minimum shutter speed at which you can safely hand hold a lens is the reciprocal of the focal length, which in the case of an 85mm lens is approximately 1/90 second, with a lot of qualifiers based on your hand-holding skills and your camera resolution. I didn’t push it as low as 1/10 second, but I was able to get exceptionally sharp results down in the 1/30- to 1/15-second range.
The SP 85mm F/1.8’s nine curved diaphram blades stay perfectly circular down to f/2.8 for a pleasing, smooth rendering of out-of-focus backgrounds. The minimum aperture is f/16 and minimum focusing distance is 31.5 inches. From wide open down to f/11 it's sharp from center to corners, but center-to-corners performance is best in the tighter f/2.8 to f/8 range, especially in the corners. At f/16 fine details are noticeably not as crisp.
Moisture barriers are installed around the AF and VC switches and also between the lens barrel and focus ring to for additional protection in adverse weather conditions.
Ellis Vener is Professional Photographer contributing editor.