Micro Four-Thirds and Telecentricity
When you go away on a vacation and deliberately stay out of touch with what's going on, you half expect the world to have changed by the time you get backand sometimes it's nice when it really does. (Sometimes it's not nice at all: war between Russia and Georgia? I didn't see that coming.)
What I mean, of course, is the really encouraging news from Olympus and Panasonic about the new Micro Four Thirds standard. My initial reaction is tempered somewhat by the fact that we haven't seen anything about implementation yet, and implementation with digital devices is crucial. But still, it's exciting.
Some of the Olympus materials about Micro Four-Thirds talk about market share, saturation, opportunity, and so forth, and, doubtless, part of what the two companies are doing is trying to wedge open a new niche with the potential to become a big category. In trying to meld together a point-and-shoot body size with the lens interchangeability and image quality of a DSLR, however, one big question is whether they'd rather the result be more like the one or more like the other. Naturally, what comes dancing in front of my eyes when I read about Micro Four-Thirds are exquisitely constructed deluxe little metal gems like miniaturized Leicas, tough and waterproof and with image stabilization and top-quality lenses, and responsiveness as sharp as a razor; but what might be dancing in front of the designers' eyes could be something completely differentlike millions of consumers with full wallets who just want slightly better point-and-shoots. Again, implementation is crucial. But when the products are announced, I hope there will be both consumer and "professional" (premium) options right from the start.
Telecentricity requirement relaxed?
One thing that seems probable is that the Micro Four-Thirds lenses will be very small. Jonathan Guilbault writes to tell me that backpackinglight.com has a very interesting article about Micro Four-Thirds by Rick Dreher, based on original interviews with Olympus reps at Outdoor Retailer Summer Market 2008. Unfortunately the article is only available to paid subscribers to the site (you can buy a single article, but only to be mailed to you in hard copy form). However, Jonathan tells me that the article reports that, as part of the new standard, Olympus and Panasonic have decided to relax the strict 100% telecentricity requirement of the full Four-Thirds standard. As you probably know, this part of the standard requires that image-forming light must impinge on the sensor at a perpendicular angle; it's a primary reason why the superb 4/3rds lenses are mostly as large as 35mm lenses (long telephotos excepted). Here's a brief quote from the backpackinglight.com article:
Of great importance, if not well understood, is the relaxation of Four-Thirds' rigid telecentric lens standard. CCD imaging chips used in early digicams need light to hit the chip surface at a perpendicular angle, as their photosites sit in depressions that off-angle light can't reach evenly. This creates havoc that the original Four-Thirds standard addressed by demanding system lenses be perpendicular (telecentric). However, newer NMOS chips new used by Olympus and Panasonic don't suffer fatally from angled light, and advanced in-camera processing can address intensity differences that still occur across the frame.
This allows the Micro Four-Thirds rear lens element to sit closer to the chip which, in turn, allows lenses to be smaller. Thus unleashed, camera and lens designers can now employ classic wide angle lens designs unusable in SLRs, create zooms with rear elements that protrude into the camera body, and shrink many lens parts.
I don't know why this wouldn't be mentioned in the official inaugural publicity about the new Micro Four-Thirds standard. But if it's true, it will be at least as important as the greatly reduced flange distance in allowing dedicated Micro Four-Thirds lenses to be significantly smaller and lighter than 35mm, APS-C, and existing 4/3rds lenses, without sacrificing optical quality.
Wait and watch
How significant is Micro Four-Thirds? Well, I don't know, of course, and I think it's dangerous to guess at this point. I think that potentially it could up-end the entire camera marketwhich could look very different a year from now as a result. But that one-word qualifier ("potentially") is still important. As robust as it is, the digital-imaging-device market is still subject to extraordinarily complex volatility. Deeper analysis is probably pointless until we see actual products.
I can tell you one thing for certain. I'll be waiting to see what Olympus and Panasonic have cooking before I buy anything new. After pining in public for several years now for just the sort of camera that one of these could turn out to be, it seems the least I should do.
