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09-22-2009, 12:55 PM   #91
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QuoteOriginally posted by falconeye Quote
Maybe, but the E-P1 is larger than the XR1, even without a lens at all (120.5 x 70 x 35 mm vs. 124 x 59.5 x 32 mm which is 25% larger in volume). And still it has the significantly smaller FT sensor. I am sure, the XR1 could be even narrower if made by a larger engineering team.

I tend to insist: current mirrorless system cameras are bulky. That's the problem, not that there is no intermediate sensor size.

There is a practical size limit based on the minimum possible flange diameter and registration distance usable on a 4/3 or APSC sensor.

The original 4/3 camera was designed specifically to minimise light falloff and corner softness and it was well executed. 4/3 lenses have less distortion and falloff than any APSC lens of similar view angle.

OTOH on micro 4/3 you can reduce the reg. distance, hence reduce the cameras depth (but not much else) but then introduce corner light falloff and spherical aberation issues that have to be corrected in camera. Fine, but its still a compromise. Any smaller, and it makes it worse. Any larger and no point.

Moreover, for a given sensor size, the minimum lens diameter for standard and tele lenses is still focal length/f-stop. So no size or weight improvements there. Hence my suggestion for a mid-size sensor. Better than P&S, smaller than APS.

They are of course cheaper to build and easier for companies that are not part of the SLR cadre. However whether the world cares about another interchangeable lens format is another thing. I reckon the target market would be just as interested in a fixed lens system with a large sensor, in which case you could use a telescoping lens design to minimise camera size when inactive, but increase the incident light angles in the corners. Similar to X1 and DP1 in effect.

I see a war brewing, but I think my initial estimates of Micro cameras killing off low end SLRs was a bit premature. I think we are just seeing the reemergence of a better quality bridge camera.

09-22-2009, 12:57 PM   #92
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QuoteOriginally posted by gazonk Quote
I agree - I'd say that the current DSLRs are still bulky, too. I bet we'll eventually see FF DSLRs as thin and low as the Pentax ME - and less wide! There's no absolute physical reason the sensor, even with shift mechanism, should take much more place than the film back plate, and no reason electronics should take more place than the film itself. It's just a matter of miniaturisation - i.e. time...
The depth is a result of the size of the rear LCD as much as anything else. You can make all of it a bit thinner, but you cant make the sensor much smaller. The whole point is to use as large a sensor as possible.
09-22-2009, 01:01 PM   #93
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QuoteOriginally posted by MikePerham Quote
I would snap up a Pentax compact like the Leica X1 with an APS-C sensor, fixed 24mm lens. This camera does not have to be an EVIL ...as a carry around camera I would be quite happy with a fixed 24mm. In fact Pentax could use the same sensor as the K-x that has the same pixel density as the Leica X1 and I am sure could compete with that camera in IQ at a considerably lower price.
Me too. Pentax version of the LX1 would be gr8.
09-22-2009, 01:21 PM   #94
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QuoteOriginally posted by *isteve Quote
There is a practical size limit based on the minimum possible flange diameter and registration distance usable on a 4/3 or APSC sensor.
You make good points and I would probably come over to your point of view, if not ....

... the Pentax 110 wouldn't have been such a great and truely pocketable FourThird film/sensor sized system camera. Its 18mm lens is highly considered in the mFT camp

09-22-2009, 01:42 PM   #95
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QuoteOriginally posted by *isteve Quote
The depth is a result of the size of the rear LCD as much as anything else. You can make all of it a bit thinner, but you cant make the sensor much smaller. The whole point is to use as large a sensor as possible.
Good point about the rear LCD screen *isteve, here is an article about Samsung's OLED/AMOLED

OLED/AMOLED screens coming to a camera near you | Photo Rumors

The advantages (From the article):

* Very thin and lighter weight
* Greatly minimized propensity for breakage
* Lower-power, highly rugged with superior image quality, and low cost
compared to the current LCD displays
* Due to their inherent ruggedness, allow a unique form factor of conformability
and rollability during use, transportation and storage.
09-22-2009, 03:07 PM   #96
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QuoteOriginally posted by falconeye Quote
You make good points and I would probably come over to your point of view, if not ....

... the Pentax 110 wouldn't have been such a great and truely pocketable FourThird film/sensor sized system camera. Its 18mm lens is highly considered in the mFT camp
I'd like to see some (undoctored RAW) image samples first...

This is not a new problem after all, its just that sensors (especially CMOS) are more sensitive to light falloff with incident angle. You can keep the reg distance but still place the exit pupil of a lens further from the film plane...

Believe me I really want micro cameras to succeed but unless they use fixed lenses, I don't see how they can make them a lot smaller.

Mind you, looking at the high ISO performance from the Canon S90, I am not sure there is not still a bit of life in the old digicam yet....

Last edited by *isteve; 09-22-2009 at 03:16 PM.
09-22-2009, 03:11 PM   #97
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QuoteOriginally posted by Angevinn Quote
Good point about the rear LCD screen *isteve, here is an article about Samsung's OLED/AMOLED

OLED/AMOLED screens coming to a camera near you | Photo Rumors

The advantages (From the article):

* Very thin and lighter weight
* Greatly minimized propensity for breakage
* Lower-power, highly rugged with superior image quality, and low cost
compared to the current LCD displays
* Due to their inherent ruggedness, allow a unique form factor of conformability
and rollability during use, transportation and storage.
Yep - that should give you about 2mm less on the depth although the main advantage in a camera installation is low power and heat combined with improved quality.

The in-camera AS though - thats purely mechanical engineering. Improvements are certainly possible, for instance by using titanium, but the cost would go up.

Compare the depth of a K100D with an old *istDS and you will see what I mean. K100D is quite a bit thicker.
09-22-2009, 10:01 PM   #98
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QuoteOriginally posted by *isteve Quote
I'd like to see some (undoctored RAW) image samples first...

This is not a new problem after all, its just that sensors (especially CMOS) are more sensitive to light falloff with incident angle. You can keep the reg distance but still place the exit pupil of a lens further from the film plane...
Hmm, CMOS sensors are more prone to light falloff? Now I had to check the specs of the sensor of the M9, and indeed - it's a CCD sensor.

09-23-2009, 04:06 AM   #99
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QuoteOriginally posted by *isteve Quote
I'd like to see some (undoctored RAW) image samples first...
I am sure they float around somewhere
QuoteOriginally posted by *isteve Quote
This is not a new problem after all, its just that sensors (especially CMOS) are more sensitive to light falloff with incident angle. You can keep the reg distance but still place the exit pupil of a lens further from the film plane...
Well, this is more a generic wide angle problem than anything else. Better microlens design (larger micro lens edge angle) and back illuminated CMOS are going to reduce the problem to the generic one.

The FT telecentric idea (make the exit pupil move away from the focal plane) doesn't work well for large apertures (you cannot change the apparent size of the exit pupil) and really shouldn't have kept for the mFT specification. It simply is a thing of the past. What remains is the effect of natural vignetting.

Natural vignetting or cosine^4 law is a universal property of the "ideal" lens. Both, retrofocus wideangle lenses and telecentric designs are less troubled by natural vignetting.

Natural vignetting light falloff is universal and for a 18mm full frame lens (12mm APS-C) the corner angle is 50░ (FoV/2), cos^4 = 0.17 or -2.6EV.

The fact that we don't see, e.g., -2.6EV corner vignetting with the DA12-24 means that it was corrected by its retrofocus construction and/or by the camera firmware. I know for sure that the Pentax firmware contains a symbol named Cosine4CorrectQuaterEv256 and you cannot enable or disable vignetting correction (only distortion and CA)... It is of course trivial to apply to raw data. I believe it is the same for every vendor. Would be interesting to measure vignetting for the DA12-24 on film

So, this bit of extra vignetting and its electronic correction for shorter registration distances may not be that bad after all

And as it is the natural vignetting, the more correct point of view is that telecentric of retrofocus designs lead to "countervignetting" of the center making large aperture SWA impossible (2.6 EV max. aperture loss at 12mm APS-C (*)).

(*) A 12mm f/1.4 ideal lens with natural vignetting and a 12mm f/4.0 telecentric/retrofocus w/o vignetting would be the same size...

Last edited by falconeye; 09-23-2009 at 04:13 AM.
09-23-2009, 05:16 AM   #100
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QuoteOriginally posted by falconeye Quote
I am sure they float around somewhere

Well, this is more a generic wide angle problem than anything else. Better microlens design (larger micro lens edge angle) and back illuminated CMOS are going to reduce the problem to the generic one.
Hopefully, but emphasis on future tense. If micro cameras become a major marketing success, then we will see more sensor research into this issue and more mass production of sensors with the appropriate lens design.

QuoteQuote:
The FT telecentric idea (make the exit pupil move away from the focal plane) doesn't work well for large apertures (you cannot change the apparent size of the exit pupil) and really shouldn't have kept for the mFT specification. It simply is a thing of the past. What remains is the effect of natural vignetting.
All this is true, but micro cameras are also constrined somewhat by their own size to keep lenses - especially telephoto and zoom lenses - relatively slow. However it should be easier to design a compact wide aperture compact standard lens at F1.0 because the focal length is only 22mm.
However without retrofocus designs, wider apertures also increase spherical aberation as well.
QuoteQuote:
Natural vignetting or cosine^4 law is a universal property of the "ideal" lens. Both, retrofocus wideangle lenses and telecentric designs are less troubled by natural vignetting.

Natural vignetting light falloff is universal and for a 18mm full frame lens (12mm APS-C) the corner angle is 50░ (FoV/2), cos^4 = 0.17 or -2.6EV.
The fact that we don't see, e.g., -2.6EV corner vignetting with the DA12-24 means that it was corrected by its retrofocus construction and/or by the camera firmware. I know for sure that the Pentax firmware contains a symbol named Cosine4CorrectQuaterEv256 and you cannot enable or disable vignetting correction (only distortion and CA)... It is of course trivial to apply to raw data. I believe it is the same for every vendor. Would be interesting to measure vignetting for the DA12-24 on film
Since its measured using dcraw, its unlikely such corrections are applied in PhotoZone tests, but they are applied to JPEGs which is why there is no vignetting in JPEGs with correction applied. Like I said I have no problem with that.
QuoteQuote:
So, this bit of extra vignetting and its electronic correction for shorter registration distances may not be that bad after all
It depends how destructive it is. Adding +2ev of exposure in the corners adds +2ev of noise, and there is nothing you can do about it. If you want to increase the overall exposure, the picture rapidly becomes unusable.
Besides, vignetting and distortion can actually be used to artistic effect - I dont want them removed by default, though I am happy to have a forumula to remove it automatically if I want to.

QuoteQuote:
And as it is the natural vignetting, the more correct point of view is that telecentric of retrofocus designs lead to "countervignetting" of the center making large aperture SWA impossible (2.6 EV max. aperture loss at 12mm APS-C (*)).

(*) A 12mm f/1.4 ideal lens with natural vignetting and a 12mm f/4.0 telecentric/retrofocus w/o vignetting would be the same size...
That may well be true, but its not just vignetting, the loss of resolution follows the same cosine formula in an uncorrected lens and this is amplified by larger apertures.

And even if your lens outresolves the sensor (unusual in current cameras) correction of distortion after the fact still reduces resolution between the input RAW file and the output one.

Now I am not saying micro cameras are a bust, I am saying that they will require an optimised sensor architecture (like Leica) to maximise the physical system performance. If you subsequently want to apply software correction, then thats fine (if optional) because it wont be nearly as destructive.

I just dont think software correction is the answer to the whole issue and I dont think the current first generation are there....yet.
09-23-2009, 07:51 AM   #101
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QuoteOriginally posted by *isteve Quote
Believe me I really want micro cameras to succeed but unless they use fixed lenses, I don't see how they can make them a lot smaller.
I personally think cameras such as the E-P1, Sigma DP2, or Canon G11 are small enough. People need to also keep in mind that a camera not only needs to be portable, but also usable. I couldn't imagine using some of the really tiny P&S's such as the Optio's for extended periods of time. Sure, they are more portable, but unless the user has tiny hands then I don't see how anyone can enjoy using them.

Despite what a lot of review sites say, I've walked around with the E-P1 in my pocket no problem. I just put the lens in my left pocket and the camera body in my right. When I don't feel like doing that I just carry a small messenger pack. I usually find the man purse is nice to have anyway when walking around a city.

I used to make the case that if you're going to carry a bag you might as well carry a DSLR...even a full frame one, but that was before I put the minuscule E-P1 in a bag an walked around all day with it. You forget it's back there. Plus you have room for whatever else you might acquire during the day...food for example. That was not the case as all with my K10D. I found myself leaving the camera and bag at home because after 4 hours I was sick of lugging it around, and my D200 was even worse obviously.

Besides, if extreme portability is what people care about they should just use a cell phone. I made an 8x10 test print of this pic taken with my iPhone 3Gs and after some processing in Lightroom if I didn't know that I took the pic with my phone I wouldn't be able to tell from looking at the print. Chase Jarvis is another big advocate of cell phone use. He's just released a book and a photo app for the iPhone based on his blog post about the best camera is the one you have on you....and make no mistake about it, cameras like the Optio's are going to go bye-bye as camera phones keep getting better and better. I personally think they are already obsolete. Sure, they are better than most cell phones, but they are still slow, have terrible noise, and seeing as how most people just take social snap shots and rarely ever make prints from them I'm willing to go out on a limb and say a 3 megapixels camera phone is all they need.
09-23-2009, 08:14 AM   #102
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Ok, I will expose how I see things (so it is just my view):

* Yes I'd like to have a camera in my jacket at all time.
* No, a G11 isn't small/light enough, I don't wanna break my jacket pockets.
* Yes an EP-1 may be OK but really dimensions the Max acceptable, if not just unacceptable (to me of course).
* No, detaching the lens is no good thing, talk about losing 1 minute each time you need a picture. (and sunset move fast), so EP1 is probably too fat for me.
* Yes sensors embedded into G11/LX3 are too small to my tastes.
* Phone? You're joking right? (pulling your legs, Art ) That's even smaller sensor and I do NOT want to change the way I take pictures every time I change my phone.

In fact, a Pentax version (read: one that can actually be bought without losing a month salary but not crappy as the Sigma) of Leica X1 could be exactly what I'm after. It may be 4/3 I don't care for that use, but no smaller sensor.
09-23-2009, 08:36 AM   #103
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I would like to see Pentax merge the best of K-7, Leica M9, and Panasonic GF-1. It would be tiny, with a solid feel, a huge articulating LCD, full compatibility with all existing lenses, and non-modal buttons or dials for aperture, shutter and ISO, responsive operation

If the LCD is really good, I can do without the optical vf.

Here are the things I don't really care about: burst rate, autofocus performance, JPEG, white balance performance, video, scene modes, water resistance, dust cleaning, super high shutter speeds, flash sync speed.

Or - here's a thought - have no LCD, just a really good EVF - the new class of camera known as "chimpless".

Last edited by Michael Barker; 09-23-2009 at 08:41 AM.
09-23-2009, 08:53 AM   #104
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QuoteOriginally posted by *isteve Quote
That may well be true, but its not just vignetting, the loss of resolution follows the same cosine formula
True.

I just wanted to highlight that an ideal telecentric (or retrofocus) wideangle doesn't have vignetting because it has even illumination of a magnitude an ideal natural lens of the same size (not optical aperture) would have in the corners (the 2.6EV difference for 12mm APS-C).

This is new insight for me. I didn't know it beforehand. The nice thing is that it gives us a formula for maximum aperture with retrofocus wide angle lenses. A formula I didn't know it exists. (The formula would take FoV and permissable corner vignetting.)

You are right that the cos^4 applies to resolution as well. But again, the center resolution of a simpler natural lens may be much higher due to its more straight-forward design and the stellar performamce of some M mount wide angle lenses seem to confirm this. So again, the same logic may apply.


In short words:

It may be that a retrofocus lens is having degraded center performance rather than a natural lens is having degraded corner performance.

I don't know for sure. But we should take this possibility into account. I believe, it makes a difference in your path of arguments.

Anyway, this consideration was new to me and I wanted to share.
09-23-2009, 11:24 AM   #105
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QuoteOriginally posted by thibs Quote
* Yes I'd like to have a camera in my jacket at all time.
* No, a G11 isn't small/light enough, I don't wanna break my jacket pockets.
Damn man, what kind of jackets do you wear? I don't own a single one that has a pocket so small that I couldn't slide the E-P1 + 20mm pancake into no problem.

QuoteOriginally posted by thibs Quote
* Phone? You're joking right? (pulling your legs, Art ) That's even smaller sensor and I do NOT want to change the way I take pictures every time I change my phone.
And yeah, I am serious about the phone. Yes, they have tiny crappy sensors, but as a result you wind up with some interesting shots sometimes...kind of like using a Holga. Plus, there are a few camera phones out there now that shoot pics every bit as nice as most pocket P&S's. Furthermore, I think using the fixed lens like most camera phones have would force people to be more creative. No, they're not ideal for serious use, but they are always with you. I don't care how small they make a camera, I will never have one with me all the time. Check out Chase Jarvis's iPhone gallery. His iPhone pics (even the first gen iPhone) are better than most Flickr galleries I look through with people using the best gear in the world.

Chase Jarvis iPhone Gallery

I recently attended a wedding and noticed the photographer had multiple 5D Mk II's...when I saw the pics after wards I thought to myself the guy might as well have been using Canon Powershot G2's. I didn't see a single photo I'd actually pay for. Pure crap. But hey, at least the images were noise free and huge!

As far as large sensor cameras go...I agree with Steve, I think the E-P1 and GF-1 are about as small as they can go. They might shave off a bit here and there, but they're never going to reach a totally unobtrusive size.
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