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06-10-2012, 01:22 AM - 1 Like   #31
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QuoteOriginally posted by lpfonseca Quote
I think so too. In my opinion the target for K-01 is the Canon G1X. But it need a collapsible zoom lens so that the size remains contained.

Compare Canon G1X and K-01 dimensions side by side

This zoom could turn the K-01 into a very interesting "large pocket" camera.
The problem with K-01 is not height or width, but rather depth...

06-10-2012, 01:43 AM   #32
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QuoteOriginally posted by Boris Quote
The problem with K-01 is not height or width, but rather depth...
Without that depth it could not take K-mount lenses on an APS-C sensor, so it would not exist.
And by the way: the depth is a non-issue in my experience, and if the lenses protrude less it is probably better than most of its competitors.
06-10-2012, 01:47 AM   #33
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QuoteOriginally posted by Sandy Hancock Quote
Without that depth it could not take K-mount lenses on an APS-C sensor, so it would not exist.
Of course. That goes without saying. It is just to say that one camera is as small as the other without taking into account all three dimensions is a bit misleading. Again, horses for courses, but I find the issue of depth rather important. Apparently I am not alone as Pentax is working really hard to produce very thing lenses, such as new XS 40/2.8 and I take it, they do so for the reason.
06-10-2012, 07:45 AM   #34
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QuoteOriginally posted by Boris Quote
Apparently I am not alone as Pentax is working really hard to produce very thing lenses, such as new XS 40/2.8 and I take it, they do so for the reason.
The following is my humble opinion, as a K-01 owner and user.

A useable K-01 (i.e. a K-01 with a K-mount lens mounted sans adapter) is roughly the same depth as a mirrorless APSc camera with a K-mount lens mounted with adapter - or, for that matter, any lens mounted, with or without adapter. In useable form a K-01 occupies similar pocket space as a smaller mirrorless APSc body with a lens mounted. The additional body depth of a K-01 permits a more stable grip, at least for me, than a smaller body.

Therefore the additional depth is rather a feature than a problem.

Q.E.D.

Pentax simply has a unique "take" on the mirroless advantage of small size.

06-10-2012, 08:21 AM   #35
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QuoteOriginally posted by Alizarine Quote
I think this will be a new release later some time... the 18-55 range is the "basic" kit FL range right?
18-55mm on APS-C is a translation of 28-80mm on 135/FF. AOV range extends from fairly wide (~75 degrees) to portrait narrow (~30 degrees) over a ~3x focal range. For m4/3 cameras that range would be ~14-40mm. I'll guess that fairly compact kit.lenses with decent but not fast optics are producible within those ranges but would have major problems being either wider-range or faster. Fast APS-C 16-45mm and 17-50mm kit.lens replacements tend to be rather large, eh? And a pancake DA 18-55/3.5-6.7 XS with huge barrel distortion would only be workable on a high-ISO body with in-camera optical corrections. Maybe that will be the K-02? Or does the K-01 bear hidden secrets?

QuoteOriginally posted by Asahiflex Quote
never mind...
I'll try. At least until my budget improves.
06-10-2012, 10:42 AM   #36
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Why do so many people worry about distortion? It only takes several seconds to correct in softwares (such as the free pentax software comes with your camera).
It is much harder to design a lens that has not only little distortion, but also good contrast and sharp. But distortion is the easiest to correct. It is a trade off. If you want a better picture, get a lens with better contrast and sharpness, then correct the distortion yourself. At least this is what I will do.




QuoteOriginally posted by RioRico Quote
18-55mm on APS-C is a translation of 28-80mm on 135/FF. AOV range extends from fairly wide (~75 degrees) to portrait narrow (~30 degrees) over a ~3x focal range. For m4/3 cameras that range would be ~14-40mm. I'll guess that fairly compact kit.lenses with decent but not fast optics are producible within those ranges but would have major problems being either wider-range or faster. Fast APS-C 16-45mm and 17-50mm kit.lens replacements tend to be rather large, eh? And a pancake DA 18-55/3.5-6.7 XS with huge barrel distortion would only be workable on a high-ISO body with in-camera optical corrections. Maybe that will be the K-02? Or does the K-01 bear hidden secrets?


I'll try. At least until my budget improves.
06-10-2012, 11:04 AM   #37
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QuoteOriginally posted by monochrome Quote
A useable K-01 (i.e. a K-01 with a K-mount lens mounted sans adapter) is roughly the same depth as a mirrorless APSc camera with a K-mount lens mounted with adapter - or, for that matter, any lens mounted, with or without adapter. In useable form a K-01 occupies similar pocket space as a smaller mirrorless APSc body with a lens mounted. The additional body depth of a K-01 permits a more stable grip, at least for me, than a smaller body.
You certainly have made a good point. The distance between the sensor and the mount is constant (flange distance/register distance) and cannot be taken away from the camera depth. Under similar reasoning I opted to buy another K-5 instead of K-01. OTOH, I am thinking about the likes of Ricoh GXR and M-module notably because the register distance of Leica cameras is smaller than that of Pentax and the standard lenses (35-50 mm) are not as deep as those by Pentax(*).

(*) According to Wikipedia Pentax flange distance is 45.46 mm, while Leica's is 27.80 mm...
06-10-2012, 01:02 PM   #38
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QuoteOriginally posted by Sandy Hancock Quote
Without that depth it could not take K-mount lenses on an APS-C sensor, so it would not exist.
The possibilities!

06-10-2012, 01:08 PM   #39
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QuoteOriginally posted by feishui Quote
Why do so many people worry about distortion? It only takes several seconds to correct in softwares (such as the free pentax software comes with your camera).
I personally don't worry much about such distortion. But a lens+camera combo that features significant distortion won't test well, will gain a bad rep, won't sell, will lose money and piss-off stockholders and management, etc. So in-camera auto distortion correction will be decreed by the marketing wonks. That's bidness.

QuoteOriginally posted by Boris Quote
The distance between the sensor and the mount is constant (flange distance/register distance) and cannot be taken away from the camera depth.
It's still possible to maintain register distance but have rear elements protrude into the register space. In fact, it's quite common. I need merely peer at the lens closest at hand (F35-70) and see that it protrudes about 5mm into that space. I've adapted lenses that protrude just over 10mm -- that's the safe limit, to avoid fouling the K20D's mirror. With an MILC, a lens could protrude ~44mm with no trouble (but a smart engineer wouldn't go past 43mm).

Last edited by RioRico; 06-10-2012 at 01:15 PM.
06-10-2012, 01:26 PM   #40
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QuoteOriginally posted by Laurentiu Cristofor Quote
AFAIK, it's corrected in RAW processing, so if you don't shoot JPEG, you can process images without correction and test for it, just like photozone does.

This seems to be the trend of the future and the idea is to focus on sharpness and let distortion and CA be corrected in software. It's always easier to optimize a single parameter than a bunch. Correction of distortion and CA can lose some sharpness in the borders, but if that is high to start with, the result will still come all right. And I imagine that not worrying about these issues can also simplify the optical design by eliminating the need for corrective elements.

So this lens would have to be significantly sharper than the current kit lens, but if that is not the case, I don't know what its point is.
It's not free. On the cheap pancake lenses like the Panasonic 14mm and Olympus 17mm, barrel distortion is very high. Correction would lose you 1-2mm of focal length turning the "35mm equivalent" lens into something closer to 37-38.
06-10-2012, 03:11 PM   #41
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QuoteOriginally posted by RioRico Quote
(...)

It's still possible to maintain register distance but have rear elements protrude into the register space. In fact, it's quite common. I need merely peer at the lens closest at hand (F35-70) and see that it protrudes about 5mm into that space. I've adapted lenses that protrude just over 10mm -- that's the safe limit, to avoid fouling the K20D's mirror. With an MILC, a lens could protrude ~44mm with no trouble (but a smart engineer wouldn't go past 43mm).
That is precisely the point of this patent that says that the back focus distance of the lens is 3mm, thus implying that the lens protrudes by 42.5mm into the register space.

This is coherent with other data from the patent, when they say that the lens's total length is 59.72mm at f=18.6mm but with only 1.5cm "flying out of the body": with a length of 59.72mm of which 42.5 are in the register space, only 17.2mm would be apparent.

This inclusion of three quarters of the lens in the inside diameter of the mount implies lenses of quite small a diameter, thus being coherent with the f/6.7 max. aperture at f=55mm.
06-11-2012, 01:19 AM   #42
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QuoteOriginally posted by monochrome Quote
Therefore the additional depth is rather a feature than a problem.
Good point, but I think they should try to reduce the weight of the successor of the K-01.
06-11-2012, 01:31 AM   #43
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QuoteOriginally posted by Mistral75 Quote
This inclusion of three quarters of the lens in the inside diameter of the mount implies lenses of quite small a diameter, thus being coherent with the f/6.7 max. aperture at f=55mm.
I still think that f6.7 is almost useless. That is by far to slow. The K-01 needs light to get its AF working proparly.

QuoteOriginally posted by gazonk Quote
Good point, but I think they should try to reduce the weight of the successor of the K-01.
To be honest I don't think the weight is a big problem. I wouldn't mind having it 20 % lighter. Having just a little better grip would help more.
06-11-2012, 01:46 AM   #44
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QuoteOriginally posted by wjjstu Quote
It's not free. On the cheap pancake lenses like the Panasonic 14mm and Olympus 17mm, barrel distortion is very high. Correction would lose you 1-2mm of focal length turning the "35mm equivalent" lens into something closer to 37-38.
I've also always assumed that correcting extreme barrel distortion reduces image quality - especially sharpness - and can lead to images that actually look 'corrected'. Sometimes as noticable as the orignal barrell distortion.
06-11-2012, 02:07 AM   #45
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QuoteOriginally posted by Caat Quote
I've also always assumed that correcting extreme barrel distortion reduces image quality - especially sharpness - and can lead to images that actually look 'corrected'. Sometimes as noticeable as the original barrel distortion.
It also leads to a reduced angle of view in comparison with the focal length: through the correction, the image is slightly cropped by the system, i.e. you loose the extreme corners.
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