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.
ARTICLE OUTLINE
- Changing Chips Alter Design Requirements
- Unanswered Questions
- Is It Really New?
- Background
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Companion forum thread to:
Micro Four-Thirds Slashes Camera Size and Weight, Retains dSLR Benefits? (Outdoor Retailer Summer Market 2008)
Not longer availiable but….
There was the very nice but expensive Epson RD1. APS-C sized sensor, 6MP by Sony (the one used by the Nikon D100) . Typical Cosina look, similar size to the M Leicas but a bit taller.
Franco
The relaxation of the telecentricity requirement is a very big deal.
One of the biggest complaints against the 4/3 format is that it failed to deliver on the smaller size it promised, at least with respect to wide angle and normal lenses (the telephotos are certainly much more compact than their 35mm equivalents).
The main reason for this is that designing & building telecentric wide angle lenses imposes additional lens elements and a larger size and weight. Non-telecentric wide angle lenses have the potential to be MUCH smaller than telecentric ones.
The comparison in the article is a good one. Here's another: compare the Olympus 7-14mm with the Nikon 14-24mm:
http://www.olympusamerica.com/cpg_section/lens/dea/products/lens/7-14_40/index.asp
http://www.nikonusa.com/Find-Your-Nikon/Product/Camera-Lenses/2163/AF-S-NIKKOR-14-24mm-f/2.8G-ED.html
The Olympus is nearly the same size, just about 1 cm smaller in diameter and length, but the Nikon at f/2.8 has twice as large a maximum aperture, and covers a full-frame image circle (which is twice the diameter & 4x the area of the 4/3 sensor)! Why are these two lenses so close in size considering the substantially larger light gathering area of the Nikkor? Because the telecentric requirement makes wide angle zooms for the 4/3 mount bigger than they'd otherwise be.
Micro 4/3 lenses will be even smaller than the potential savings in size implied by the above comparison. Without a mirror box retrofocal designs will be unnecessary (the Nikkor is a retrofocal design), which should further reduce the size of wide angle lenses in particular. No telecentricity, and no need for retrofocal designs means MUCH smaller wide angles –as Rick suggests, the rangefinder-size designs are once again in reach.
But with a 4/3 sensor Olympus and Panasonic can go way past the rangefinder designs, which needed to project an image circle TWICE the diameter of the one needed for a 4/3 sensor. So… these have the potential to be seriously compact, seriously high quality cameras.
P.S. I passed this news on to Mike Johnston:
http://theonlinephotographer.typepad.com/the_online_photographer/2008/08/micro-four-thir.html
He felt it was a significant event, saying: "I think that potentially it could up-end the entire camera market—which could look very different a year from now as a result." He subsequently notes, of course, that until we see actual products, all we know is the potential of the format. There's a photographic grave yard full of great ideas which were pulled off ineptly.
Incidentally, the Online Photographer is the best photography blog I've found, focused as it is less on the gear head minutiae (which he knows very well, particularly lenses)and more on the art of photography.
I've owned and used extensively many film SLR's. After much research, purchased the Nikon Coolpix L5 as part of an overall gear-lightening effort about 2 years ago. Why?
1. Nikon's reputation
2. 7.2 megapixels
3. 6 oz weight
4. NON proprietary batteries (uses AA's)
5. 5 x optical zoom lense
I have come to love this camera. It cost me about $240, it can now be had for much less: http://www.refurbdepot.com has them at $125 refurbished.
thanks for visiting,
TheThriftstoreMountaineer
The first hardware is from Panasonic–the DMC-G1
More here, with surely a lot to come before Photokina.
http://www.fourthirdsphoto.com/g1/
Body only: 385g (not as light as I suspect we'll eventually see). Interesting is a nearly 1.5MP EVF. I've never seen one with that much resolution.
I'd look for Oly to come out first with respectably small and light system lenses, probably when they launch their first body. However, Panny's lens roadmap has some interesting glass ahead as well, including a 20/1.7 prime and a 7-14/4.0 superwide zoom.
http://panasonic.jp/dc/g1/small.html
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