Plugged In: Focus on optics worth their price tag

By Joe Kashi, for the Redoubt Reporter

­Compact-camera systems from Sony, Fujifilm and Samsung share a common weakness — the lack of a wide range of modern lenses. Micro Four-Thirds cameras, in contrast, benefit from a very broad selection of high-quality, generally affordable optics.

That wide selection of good lenses is the most significant advantage of Micro Four-Thirds cameras compared to other compact-system cameras.

I’ve personally tested nearly all of the M 4/3 lenses discussed this week, confirming my own observations with data from reputable lens test sites, including http://www.ephotozine.com, http://www.slrgear.com, http://www.lensrentals.com, http://www.photozone.de and http://www.dxomark.com. These sites are excellent resources, with data about a very wide variety of interchangeable lenses. You’ll not only identify the best lenses for your needs but also the sharpest magnifications and apertures for each lens.

With very few exceptions, zoom lenses are noticeably less sharp than single-magnification “prime” lenses. Zoom lenses with a wide magnification range, roughly more than three times the widest setting, are generally less sharp, although Tamron’s new 14- to 150-mm M 4/3 “travel zoom” shows good overall sharpness in published tests.

All cameras lenses have a “sweet spot,” the point at which a lens provides its best image quality. Usually, lenses are sharpest at the center, with sharpness and contrast dropping off toward the edges and corners. Better lenses have less variation between center and corner. The optimum lens aperture for M 4/3 lenses is usually in the f/4 to f/5 range.

The smaller sensors used in M 4/3 cameras require shorter focal length lenses to achieve equivalent image magnification and field of view (how much is included in the image from edge to edge). Compared to standard, 35-mm, full-frame and film cameras, an M 4/3 camera uses a smaller lens with half the focal length to achieve comparable visual effects.

To find the equivalent 35-mm magnification of an M 4/3 lens, multiply its focal length by 2. Thus, a 25-mm lens used on an M 4/3 camera produces visual effects equivalent to the traditional 50-mm standard lens on a 35-mm film or full-frame camera, while a 12-mm M 4/3 lens acts like a 24-mm ultrawide-angle optic.

We’ll start with zoom lenses, moving from ultrawide-angle through ultratelephoto models. Only Olympus and Panasonic make M 4/3 zoom lenses. Panasonic’s 7- to 14-mm, ultrawide-angle zoom is large, well regarded and very expensive. I’m not at all sure it’s worth the price, unless you really need that ultrawide 7-mm setting. Olympus recently announced a similar, M 4/3 “PRO” lens. I’d wait and compare the two. Prices will likely drop now that there’s competition.

Olympus made two ultrawide zoom lenses with a 9- to 18-mm range. The current M 4/3 M. Zuiko version is quite a bit smaller than the older version intended for Olympus’ earlier dSLR 4/3 cameras. The older version, available used, is sharper in my experience and mounts on M 4/3 cameras via Olympus’ MMF-2 fully automatic adapter. I have both and prefer the image quality of the older ED version, but the current M.Zuiko model is adequate for most needs.

If you like superwide fisheye effects, then Rokinon’s 7.5-mm, manual focus, fisheye lens has excellent optical quality for about $270. Olympus’ 9-mm body cap fisheye isn’t as good toward the edges but it costs under $100.

Among high-end, wide-angle to short-telephoto M 4/3 zooms, there are really only two choices, Panasonic’s 12- to 35-mm model and Olympus’ 12- to 40-mm zoom. Both are excellent and similarly priced.

I decided on the Olympus 12- to 40-mm model and it’s likely the best lens I’ve ever used, sharp and with good contrast at all settings. I cannot find any flaw in this lens except some very minimal lens barrel wobble when it’s fully extended to the 40-mm setting. If you only buy one high-quality lens for your M 4/3 camera, save up for this one. In fact, it’s better than many prime lenses in its zoom range. Olympus also makes a less-expensive, 12- to 50-mm zoom that’s decent but not great. At least it’s weather resistant and has a good macro mode.

Among the kit zoom lenses included with most purchases, the current 14- to 42-mm kit zooms from both Panasonic and Olympus are very good but, again, not great. Somewhat better, and definitely more compact, is the new Olympus 14- to 42-mm EZ electric zoom model. I was so impressed by the high sharpness in such a small package that I recently bought one. Similarly, Panasonic’s tiny 12- to 32-mm kit zoom for their pocketable GM1 has good optical quality for its small size and low cost.

I’m less impressed by the affordable telephoto zoom lenses for M 4/3 cameras, and I’ve tried nearly all of them. Panasonic’s consumer telephoto zooms never seemed to produce truly sharp images for me, an experience generally confirmed by published test results.

Olympus’ consumer telephoto zoom, the M.Zuiko 40- to 150-mm, is considered the sharpest M 4/3 consumer-grade telephoto zoom, as well as the least expensive. I’ve tried several and have found one or two adequate copies. Adequate but not great. It’s worth carrying when you occasionally need a light and inexpensive telephoto zoom for casual shots.

Olympus’ newer, 75- to 300-mm II super telephoto zoom is noticeably better and noticeably larger. After comparing it to Panasonic’s competing 100- to 300-mm model, I bought the Olympus 75- to 300-mm II model. It’s definitely sharper, at least for me.

In the professional price range (read: more expensive than I’m willing to pay), Panasonic’s 35- to 100-mm zoom receives praise, but closer examination of published DXO test data suggests that its sharpness isn’t worth the $1,500 asking price. Olympus should ship its new “PRO” 40- to 150-mm model soon. I suspect this lens will be very good but bulky and expensive.

Among wide-angle prime lenses, Olympus’ 12-mm ultrawide-angle receives praise but the tiny, much less expensive Panasonic 14 mm is nearly as wide and virtually as sharp. It’s the better buy for most of us. I have one and like it.

There’s a lot of competition among 15- to 20-mm, moderate wide-angle prime lenses. Panasonic’s 15- and 20-mm primes and Olympus’ 17-mm f/1.8 prime lens are all excellent. Except in the corners, Sigma’s 19-mm DN “Art” model is nearly as good as the top three but more affordable, priced well under $200.

In the 25- to 30-mm “normal” range, the Panasonic-Leica 25-mm f/1.4 is generally the top-rated lens and priced accordingly. In my experience, though, it suffers from too much lens flare. Olympus’ new 25-mm f/1.8 isn’t quite as sharp but it’s less expensive and with lower flare. Sigma, again, provides a very sharp and economical alternative with its 30-mm “Art” lens, costing about one-third the price of the 25-mm Panasonic.

There’s a nice range of high-quality M 4/3 “short telephoto” lenses suitable for both portraiture and general use. Olympus’ 60-mm macro lens is very good, though not quite as sharp as Panasonic’s more expensive 45-mm macro lens. Olympus’ 75-mm f/1.8 telephoto is expensive but superb and worth its high price. It’s among the sharpest lenses tested.

The least expensive high-quality lenses in this magnification range are Olympus’ 45-mm f/1.8 and Sigma’s 60-mm “Art” models. Both are excellent.

There are currently no compact, affordable yet sharp M 4/3 telephoto prime lenses beyond Olympus’ 75-mm f/1.8 model. For the moment I use older, manual-focus 100-mm Pentax and 135-mm Leica lenses with adapters. On my Olympus cameras, they’re sharp and stabilized, although slow to focus accurately.

If I were buying a set of compact, sharp and affordable M 4/3 prime lenses on a tight budget, I’d buy Panasonic’s 14- and 20-mm models, Sigma’s 30- and 60-mm “Art” lenses and the 45-mm f/1.8 Olympus. I’d consider adapting a good, older, manual-focus, high-magnification telephoto lens.

On the other hand, for about the same price, you could simply buy the larger but very sharp Olympus 12- to 40-mm zoom and supplement it with a fast prime, like the 20-mm Panasonic, and a compact short telephoto, like the 60-mm Sigma.

Local attorney Joe Kashi received his bachelor’s and master’s degrees from MIT and his law degree from Georgetown University. Many of his technology and photography articles can be accessed through his website, http://www.kashilaw.com.

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