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08-07-2008, 02:38 PM   #61
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QuoteOriginally posted by Pål Jensen Quote
2. Built in hyperfocal distance auto doesn't work as the hyperfocal point depends of the size of the end results. Thas why only Canon have done it (and abandoning it I think).
I don't follow. Once you've got your sensor you can pick a conservative circle of confusion number. Then hyperfocal distance depends only on two variables the camera knows already: the focal length and f-number. Hit a button and the camera focuses to the correct distance.

QuoteOriginally posted by Pål Jensen Quote
I've never understood the balancing issue. I don't balance cameras. I photograph with them. But most of the time they are dead weight I carry around while finding something to shoot...
I am with you there. People praise lightweight lenses for being light, then turn around and praise heavy lenses for balancing better. I find this amusing.

08-07-2008, 04:14 PM   #62
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QuoteOriginally posted by rparmar Quote
the focal length and f-number. Hit a button and the camera focuses to the correct distance.
You're right and such a function could come with any firmware upgrade

However, to be honest, the user would have to be allowed to enter an anticipated crop factor as well. Because the hyperfocal distance depends on the fraction of the image you are going to print. It was easier in film days where almost always this fraction was 100% This may be more important with primes than with zooms, though.
08-07-2008, 04:20 PM   #63
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QuoteOriginally posted by Art Vandelay II Quote
I just don't see where APS-C SLR's will fit in.
I'm glad you said this. Both, 43 and FF have their markets which are clearly separated by 2 stops of light and a significant factor in size and weight. And soon there will just be no niche in between for APS-C.

Having said this, I nevertheless don't understand why FF cameras can't be very small too. MX size is very feasible (was done 30 years ago...) after all.
08-07-2008, 05:06 PM   #64
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QuoteOriginally posted by falconeye Quote
You're right and such a function could come with any firmware upgrade

However, to be honest, the user would have to be allowed to enter an anticipated crop factor as well. Because the hyperfocal distance depends on the fraction of the image you are going to print. It was easier in film days where almost always this fraction was 100% This may be more important with primes than with zooms, though.
Sure you can, but you can also set hyperfocal distance on the lens and make your own conservative estimate, or aternatively, use the DOF preview. These are far more elegant solutions with the benefit of not using electricity (DOF previev can depending on how it is implemented). Both non-optical viewfinders (as replacement for an optical) and auto hyperfocal distance auto are solution to non-existing problems, like power zoom and power focus. Having no optical viewfinder is a disadvantage in terms of ergonomics and usability, but an advantage for size...

08-07-2008, 05:15 PM   #65
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QuoteOriginally posted by Pål Jensen Quote
Both non-optical viewfinders (as replacement for an optical) and auto hyperfocal distance auto are solution to non-existing problems, like power zoom and power focus.
It's pretty hard to set the hyperfocal distance on a zoom, since they generally do not have any markings on the lens barrel to help. And I am crap at estimating distance.
08-07-2008, 06:48 PM   #66
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compact body meet ZD ED14-35mm F2.0 SWD

Got one Oly buddy demonstrate when compact body meet ZD ED14-35mm F2.0 SWD. This is how it will look:


08-07-2008, 07:12 PM   #67
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QuoteOriginally posted by take Quote
Got one Oly buddy demonstrate when compact body meet ZD ED14-35mm F2.0 SWD. This is how it will look:
That does look pretty silly, hopefully the M4/3's zooms will be smaller. Not that I really care, give me a 12mm f/4, 25mm f/2.8 and 40mm f/2.8 pancake primes and I'll be happy as I can be.

Although, that pic does kind of remind me of most SLR's I've seen mounted on to 400mm+ primes, and they manage to make it work
08-07-2008, 07:34 PM   #68
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I like the micro-4/3 concept, a big sensor in a compact body, like the Sigma DP1. But it remains to be seen if this concept will have a real commercial success. We already know that in this regard the DP1 is a total failure. A M4/3 can stand more chance if implemented well but it will probably never overcome the downside of big sensors: limited focal range. For the public used to 3x, 5x and even 10x (Panasonic TZ5, Canon SX100...) on a compact body, how to sell a camera with a prime lens or a very limited zoom range?

The other thing is that it's just a concept announcement, nobody (well almost, since Phil Askey hinted that a real product maybe not too far) knows if and when they will have a real camera with a M4/3 lens.

08-08-2008, 12:03 AM   #69
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There is also the problem with dust for camera without mirror, but with interchangeable lenses. Don't forget that such small camera won't has Shake Reduction system like E-420 has not.
08-08-2008, 12:04 AM   #70
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QuoteOriginally posted by Art Vandelay II Quote
That does look pretty silly, hopefully the M4/3's zooms will be smaller. Not that I really care, give me a 12mm f/4, 25mm f/2.8 and 40mm f/2.8 pancake primes and I'll be happy as I can be.

Although, that pic does kind of remind me of most SLR's I've seen mounted on to 400mm+ primes, and they manage to make it work
Even 2 times smaller than 14-35 is big for small camera.
Smaller and slower. Of Course.
08-08-2008, 12:34 AM   #71
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QuoteOriginally posted by rparmar Quote
For those who object that focusing would be difficult without a viewfinder, I answer that this is just one of the compromises rangefinder users already live with.
Not really. Rangefinder focusing is certainly worlds apart from SLR focusing, but I actually find it easier to get fine focus, especially with wide lenses.

Will
08-08-2008, 01:50 AM   #72
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QuoteOriginally posted by ManuH Quote
For the public used to 3x, 5x and even 10x (Panasonic TZ5, Canon SX100...) on a compact body, how to sell a camera with a prime lens or a very limited zoom range?
For my argument, I will first have to prepare some facts. By "mFT, FT, mPK, PK" I mean the micro4/3, 4/3, Pentax APS-C and Pentax FF K mount specifications. Here we go:

Image Circle Diameter ICD (mm / crop-factor):
mFT: 21.63 mm / 2.00
FT: 21.63 mm / 2.00
mPK: 28.12 mm (K20D) / 1.54
PK: 43.27 mm / 1.00

Mount Hole Diameter (mm / %ICD):
mFT: ~42 / 194%
FT: ~48 / 222%
mPK: 47 / 167%
PK: 47 / 109%
(original M42 was 97%. So even ~100% isn't or wasn't ambitious and originally only introduced for f/1.2 lenses. The early "digital" requirement for larger mounts was lifted due to advances in micro lens technology.)

Flange Back distance (mm / %ICD):
mFT: ~19.3 mm / 89%
FT: ~38.67 mm / 179%
mPK: 45.46 mm / 162 %
PK: 45.46 mm / 105%
(limited by mirror box to >56%. So even a figure ~100% isn't or wasn't ambitious)


Now my argument:

Both, FT and mPK are ill-defined standards with way too large measures for the given image circle. mFT actually only brings these measures back to normal as we already had for PK. Therefore, going full frame will do the same trick for Pentax.

(ok, the mFT mount hole is still huge -- but a lens isn't forced to be equally large and Olympus got their own legacy problem with FT lenses here ).

This does also mean that a FF lens can be scaled down 1:2 to get a lens with equal relative resolution (ignoring diffraction, of course), field of view and aperture in F-stops.

One such example is the Sigma 28-300mm F3.5~6.3 DG Macro (Full Frame). It is 74 x 86 mm (diameter x length) and 490 g.

A corresponding 10x mFT zoom would then scale to these properties:

Olympus 14-150mm F3.5~6.3 10x Macro (mFT). It is 37 x 43 mm (diameter x length) and 80 g.

I ignored here a 44 mm flange diameter and rounded the x 1/8 weight-factor up to allow for materials not exactly made thinner by 1/2.


QuoteOriginally posted by ogl Quote
There is also the problem with dust for camera without mirror, but with interchangeable lenses. Don't forget that such small camera won't has Shake Reduction system like E-420 has not.
Any size camera can have shake reduction. Even P&S do. E.g., the Pentax SR subsystem is relatively small and very thin.

QuoteOriginally posted by take Quote
Got one Oly buddy demonstrate when compact body meet ZD ED14-35mm F2.0 SWD. This is how it will look:
Argument not valid. Cf. above. FT wide angle lenses had to be unneccessarily large because of their 179% flange back distance.

Last edited by falconeye; 08-08-2008 at 02:24 AM.
08-08-2008, 05:12 AM   #73
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QuoteOriginally posted by falconeye Quote
You're right and such a function could come with any firmware upgrade

However, to be honest, the user would have to be allowed to enter an anticipated crop factor as well. Because the hyperfocal distance depends on the fraction of the image you are going to print. It was easier in film days where almost always this fraction was 100% This may be more important with primes than with zooms, though.
So, in my suggested implementation of this function (see this old thread) one would set the acceptable level of circle of confusion.

This could probably be implemented in a non-technical way in the menus — like we now have ★, ★★, ★★★ for JPEG quality, there could be ◦, ○, O, ◯ for "hyperfocal circle".
08-08-2008, 05:55 AM   #74
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QuoteOriginally posted by wiyum Quote
Not really. Rangefinder focusing is certainly worlds apart from SLR focusing, but I actually find it easier to get fine focus, especially with wide lenses.
That is the compromise right there. Rangefinders are great for wide to normal angles but not for telephoto or macro. There are parallax issues etc. Getting fine focus with wide angle lenses is always easy. At 100mm 1:1 macro -- not so.
08-08-2008, 06:11 AM   #75
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QuoteOriginally posted by ogl Quote
Even 2 times smaller than 14-35 is big for small camera.
Smaller and slower. Of Course.
Gotta give up something I suppose. I can live with that. However, if you go by what the imaging resource predicts and cut the length of that lens in half; and the diameter down to the new M43's standard then I don't think it will be too unwieldy. But keep in mind they chose to mount Olympus's largest standard zoom on there for the the photo. The 14-35mm f/2 is twice as long as their kit 14-42mm f/3.5-5.6, 20mm longer than their 12-60mm f/2.8-4 (a lens I'd rather have), and 40mm longer than their 14-54mm f/2.8-3.5 (another very attractive lens).

I do think it's nice that Olympus is making an adapter for their current lenses (considered by some to be the best in the industry at the moment), but I have no intentions of buying any of their current lenses for this new standard, and I doubt many other people will either. That's just a nugget they're throwing current Olympus users so not to piss them off too much.

Edit: One more thought. I do agree with theonlinephotographer.com in saying that Olympus is the leader in lens design in the digital era. However, I think only in zooms. I think Pentax leads the way in primes. That's why I really hope Pentax will consider joining the consortium (if they don't make an APS-C equivalent). I'd love to make a kit mixed with Olympus zooms and Pentax primes.

Last edited by Art Vandelay II; 08-08-2008 at 06:27 AM.
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