Shooters committed to the Four Thirds System, take note. Here is Serious Glass. This pro-caliber 70-200mm equivalent zoom ($2,200, street) -- the world's fastest in its focal-length range -- packs four elements of ED glass, one element of Super ED glass, and all-metal construction with rubber seals to keep out moisture and dust.
This matte-black behemoth has a rubberized and ribbed focusing collar and knurled zoom ring. The former is smooth-turning; the latter, somewhat stiff and overdamped. Four soft-touch, AF-lock buttons surround the outer lens barrel, and the lens both focuses and zooms internally. There's also a removable tripod collar, and three-way focus-limiting switch: close-up (1.4 to 3 meters), nonclose-up (3 meters to infinity), and full ranges.
In the lab:
A true optical standout by almost all measures, the lens produced SQF sharpness/contrast numbers in the Excellent range at 35mm and 100mm, and "Double Excellent" at 75mm, with most scores at or above the 90th percentile; its lowest score was an admirable 79.4%. Ditto for distortion. DxO Analyzer 2.0 tests found only Imperceptible pincushion distortion at 35mm, 75mm, and 100mm (0.04%, 0.06%, and 0.08%, respectively). As for light falloff, we found marginal evidence of it at 35mm and 100mm (gone by f/2.5), and none detectable at all at 75mm. At the uniform close-focus distance of approximately 48.5 inches, maximum magnification ratios ranged from 1:22.8 at 35mm to 1:8.77 at 100mm -- for macro mavens, that's the Achilles' heel.
It's heavy and -- ouch! -- expensive, but it promises optical performance that, in many circumstances (low light with moving subjects, for example), could give a pro a significant competitive edge.
35-100mm (34.24-93.96mm tested), f/2 (f/1.99- 2.02 tested), 21 elements in 18 groups. Focusing turns 460 degrees counterclockwise. Zoom ring turns 60 degrees clockwise. Focal lengths marked at 35-, 50-, 75-, and 100mm.
• Diagonal view angle: 34-12 degrees.
• Weight: 4.04 lb.
• Filter size: 77mm.
• Mount: Olympus AF Four Thirds.
• Included: Lenshood, softcase, tripod mount.
• Street price: $2,200.
Subjective Quality Factor