After a six-year absence from the high-speed pro macro market, Tokina jumps back in with this 100mm f/2.8 AT-X. Unlike its predecessor, the 90mm f/2.5 AT-X, the newcomer is a true macro lens (focusing to 1:1)-a clear improvement over the defunct 90mm that focused only to half-lifesize.
Like the 90mm, however, the new 100mm f/2.8 handles bellows extension in a different way than (almost) any other macro lens. Bellows extension, a phenomenon common in large-format photography, refers to the light falloff that occurs when the lens aperture moves away from the image plane during focusing. With most S LR lenses, the movement is negligible, but with 1:1 macro lenses, which by design require relatively long travel to go from infinity to maximum magnification, the bellows factor ( i.e., the amount you must adjust exposure to comoensate for the diminished light transmission) can be considerable. W ith this Tokina, for example, the image plane receives two stops less light at close focus than at infinity. When using most 1:1 macro lenses on today's AE SLRs; as you focus from infinity to 1:1, the AE system's aoerture readout remains constant as shutter speed lengthens to compensate for the light loss. This Tokina is the same, except for this: the aperture readout also changes as focus moves closer, going lroml /2.8 to f/5.6.l t's an indicationo f the effective aperture, not the actual aperture. Don't be alarmed. At maximum aperture, you're still getting the depth-of-field of an f/2.8, even though your camera's LCD says f/5.6.
Another unusual trait: the focus-rangel imitations ystem. Most close up lenses with focus limiters offer full- and non-macro ranges, but this Tokina has a single two-way switch that provides three options. lf you focus outside the macrorange (i.e.,1 : 2 to infinity), and switch from Full to Limit, the focusing system permits only non-close-up subject distances (which is great for portraitists). Conversely, if the lens is focused between 1:1 and 1:2, andyou switch from Full to Limit, it focuses only within the close-up range (a boon to insect and jewelry photographers, among others). The third option is, of course, the full-focusing range. Sigma's 105mm f/2.8 DG Macro operates similarly.
Physically, the Tokina 100mm f/2.8 is average in size and weight for its class, and has a large, knurled focusing ring (rubberized); matte-black crinkle finish; and ampsized focus, depth-of-field, and magnification- ratio scales.( Meters are in yellow; feet in white; magnification ratios in blue.) The manual-focus action is long (as with most true macros). and extremely well-damped.
IN THE LAB
SQF data indicates excellent performance at all tested apertures and magnifications. The distortion perormance is among the best we've ever seen-minimal pincushioning (0 .340%) according to DxO Analyzer tests. Light falloff was undetectable by f/4, about average for this lens class. At the close-focus distance of 11.8 inches (1:1), center sharpness was excellent from f/2.8-22 and very good at f/32. Corner sharpness was excellent across the entire aperture range, with best performance at f/l 1. These are among the best lab results we've produced from a 100mm/105mm f/ 2.8.
Covering the full 35mm frame, this pro-grade macro is optimlzed for DSLRs thanks to improved multi-coatings that suppress reflections off digital sensors. With its superb distortion and sharpness performance, three focusing ranges, and 1:1 maximum magnification, this lens is a superior short-tele professional macro lens. And pricing? Tokina and Sigma's pro macros are each about $399 (street), and Tamron's is $450 with rebate. Nikon and Canon, meanwhile, get between $500 and $650 street for their comparable glass. The new Tokina forces the question: Are the others worth it? Tough call!
100mm (97.02mm tested), f/2.8 (f/2.91 tested), 9 elements in 8 groups. Focusing turns 120 degrees clockwise.
• Diagonal view angle: 24 degrees.
• Weight: 1.11 lb. n Filter size: 55mm.
• Mounts: Canon AF, Nikon AF.
• Included: Lenshood. n Street price: