Olympus Digital SLR Cameras and Lenses-03
Nomenclature
One of the nice things about Olympus is that they don't attempt to snow consumers with obscure acronyms. Nor does Olympus tack on fancy German brand names to lenses that they design and build. The Olympus America lens page refers to "super high grade", "high grade", and "standard" lenses.
"ED" is extra-low dispersion glass, a more expensive and higher-quality glass that reduces chromatic aberration or color fringing. All but the crummiest Olympus lenses include at least one ED element.
"Super ED" is, presumably, a newer more effective version of "ED", glass that reduces chromatic aberration or color fringing. Olympus does not explain what this means any more than Dean Wormer explained "double secret probation."
"SWD" is Supersonic Wave Drive, a piezoelectric motor that contributes to smooth and silent AF operation, similar to USM (ultrasonic motor) on Canon or AF-S (silent wave motor) on Nikon lenses.
"OM" are old Olympus film system lenses; they don't work on the modern bodies without Olympus MF-1 OM Adapter, $85. Even with the adapter, Olympus recommends for each lens a limited range of apertures, e.g., f/5.6 and f/8 for the old 85/2 lens.
All Olympus lenses incorporate modern multilayer anti-reflective coatings to improve contrast and light transmission. Mercifully Olympus does not have a brand name for their coating.
History
In the 1970s, Canon and Nikon were slugging it out with cameras that were progressively more capable, more rugged, and heavier. By the end of the decade, each company made SLRs that could be used to drive nails, capture the fastest sports cars, and weigh down the dead bodies of your enemies, dumped into the local river. Olympus took an alternative tack, introducing the light and compact Olympus OM-1 in 1972. Olympus delivered the fundamentals: bright viewfinder, through-the-lens metering, in-viewfinder displays, high quality lenses, and state-of-the-art electronics. These were delivered at roughly the same price as Canon and Nikon, but with a smaller size and lighter weight.
With a smaller market share and less capital than Canon or Nikon, Olympus came up with a feeble response to the demand for autofocus, gradually ceding market share to Canon EOS and Nikon AF. The OM-4 was the last camera of the line, introduced in 1983 and finally killed off in 2002.
(More: see the photo.net guide to the Olympus OM system.)
By the year 2000, the Olympus OM system was a collectors' item and had very few day-to-day or professional users. This gave Olympus the freedom to chuck the frame size, lens mount, and legacy users. At the time, the Canon and Nikon digital SLRs on the market were small sensor models, wasting much of the image circle cast by the big legacy designed-for-film lenses. The challenge of engineering a consumer-priced 24x36mm sensor seemed insuperable (see "The rationale for a new standard format" for an explanation). To an engineer, this was a ridiculous situation, as silly as a Nikon film photographer walking around with a bag of Hasselblad lenses designed to cover the 6x6cm medium format frame. The Olympus folks got together with a couple of partner companies and standardized a sensor size that would be reasonable to fabricate and a lens mount that would be correctly sized for the sensor size. The result was the Four Thirds system, with its 13x17mm sensor, which results in a 2X multiplier for effective lens perspective, e.g., a 25mm lens gives a normal perspective on an E-system camera, similar to a 50mm lens on a 35mm film camera.
(More: see www.four-thirds.org, quite possibly the world's worst-designed Web site.)
Normal Lenses
A normal lens is light in weight and approximates the perspective of the human eye. The focal length of a normal lens for the 13x17mm Four Thirds sensor should be between 22 and 25mm (compare to 43-50mm for a 35mm film camera). Normal lenses generally have large maximum apertures, indicated by small f-numbers such as f/1.4 or f/1.8, and therefore gather much more light than zoom lenses. It may be possible to take a photo with a normal lens in light only 1/8th or 1/16th as bright as would be required for the same photo with a consumer-priced zoom lens. Also, the viewfinder will be brighter and therefore easier to use in dim light, due to the fact that the large maximum aperture stays open for viewing and stops down to whatever aperture you have set just before taking the picture.
- Panasonic Leica 25/1.4, 525g, $800. Made in Japan by Panasonic from a design developed in collaboration with Leica, this is the only prime normal lens in the Four Thirds system. The subjective quality factor results in the Popular Photography review show that this lens does not perform significantly better than the $200 Pentax 50/1.4 or $300 Canon and Nikon 50/1.4 normal lenses. With a smaller image circle to generate, one would expect Four Thirds system lenses to be lighter, cheaper, and better quality than lenses that cover the 24x36mm frame. In fact, this lens is twice the weight and three or four times the price of an equivalent quality lens from the film world. When you've stopped moaning about the hole in your wallet, the lens is sure to be a great performer, though.
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