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04-24-2012, 07:17 AM   #61
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QuoteOriginally posted by DaveHolmes Quote
It's OK... I'm not a pessimist... I'm a cynic :-p
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04-24-2012, 05:22 PM   #62
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QuoteOriginally posted by Blue Quote
The 40 XS is on the Road map and is a k-mount. K-mount lens work on the k-01. Like I said, it is the LTD zoom it is collapsed. The zoom range on that LTD on the map isn't very long.
either way, you can't zoom without a zoom ring.
"it is the LTD zoom it is collapsed" what does that mean?
04-24-2012, 05:42 PM   #63
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QuoteOriginally posted by parsons Quote
either way, you can't zoom without a zoom ring.
"IFit is the LTD zoom, it is collapsed" what does that mean?

Fixed the quote so its not out of context. A collapsible lens has a collapsed position when it is not in use. Here is a recent design by Pany for the m4/3. If it is, it is in the collapsed position in the pic and would be focused by the barrel not shown except in collapsed position.

Panasonic Lumix G X Vario PZ 14-42mm F3.5-5.6 ASPH Power OIS Hands-on Preview: Digital Photography Review

There is a similar lens that has been out for a while by Oly. These designs existed for some of the Leica's as well. That picture is of a mock up of a lens of Limited style and build. However, you have failed to point out any other guess on the road map. That rear element is going to be to close for the existing registration distance of the K-01. That is why I think it could be a collapsible design. It is just a guess so don't soil your nickers.


Last edited by Blue; 04-24-2012 at 05:50 PM.
04-24-2012, 11:16 PM   #64
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But this is a prime lens, you can clearly see the focus ring and... no zoom ring. It's not collapsible, either.
Definitely not the Limited zoom.

04-25-2012, 01:40 AM   #65
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QuoteOriginally posted by Kunzite Quote
But this is a prime lens, you can clearly see the focus ring and... no zoom ring. It's not collapsible, either.
Definitely not the Limited zoom.
well that lens is one of the limited's. Could be 15mm/f4xs or 21mm/f3.2xs. I hope it is new lens like 28mm/f2.8xs or 24mm/f3.0xs since then there is a real new lens.
04-25-2012, 02:31 AM   #66
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Even if it would be 21 or 15 it would still be a completely new lens. Aside file of view, quality of image and sitortion would be different, being the optical path totally different.
04-25-2012, 06:58 AM   #67
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QuoteOriginally posted by Kunzite Quote
But this is a prime lens, you can clearly see the focus ring and... no zoom ring. It's not collapsible, either.
Definitely not the Limited zoom.
You fail to understand that a collapsible lens extends the tube which then could be used for manual focus or zoom. However, like I said, it is just a guess. What is your "guess" on why the rear element will be too close to the sensor for the 45.46 mm registration distance of the Pentax K-01 and dSLR bodies? BTW, where is it on the Road Map? It could be a collapsible LTD prime, somewhere between 21 and 35mm or less than 15mm. However, no one knows what a DA LTD zoom looks like except the Pentax engineers. Furthermore, there are zoom lenses with a "one touch design" with the same tube used to focus as well as zoom.

Last edited by Blue; 05-06-2012 at 04:24 PM.
04-25-2012, 09:30 AM   #68
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I'm sorry, but "failure to understand" is not something that happens to me often.

Almost always, the simplest explanation is the truth. What I see in the picture? A Limited-like lens, with a single ring - that would be the focusing ring as it has the distance scale, and which protrudes quite deep inside the lens mount (thus not being fully K-mount compatible, but designed for the mirrorless range. Maybe it could work on future APS-C DSLRs, too - not sure of that). We can start making assumptions, but that's IMHO the simplest explanation: we have what we're seeing, and nothing more.
Where is it on the roadmap, as it doesn't seems to fit anywhere? Again, the simplest explanation would be: this lens is not on the K-mount roadmap.

There are 3 questions you should ask yourself:
- does it really make sense to have a nice focus ring, but zoom by twisting the barrel itself?
- where is the collapsing/extending mechanism? How is it operated, how about barrel travel - since the lens is so short?
- does it make sense to have a collapsible wide prime? Taking the picture as a reference, you'd have the barrel extends (with the lens set to infinity) by as much as the protrusion, maybe more. It would easily be longer than the 70mm (which is remarkably short, without the lens hood)

04-25-2012, 10:01 AM   #69
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QuoteOriginally posted by Kunzite Quote
I'm sorry, but "failure to understand" is not something that happens to me often.

Almost always, the simplest explanation is the truth. What I see in the picture? A Limited-like lens, with a single ring - that would be the focusing ring as it has the distance scale, and which protrudes quite deep inside the lens mount (thus not being fully K-mount compatible, but designed for the mirrorless range. Maybe it could work on future APS-C DSLRs, too - not sure of that). We can start making assumptions, but that's IMHO the simplest explanation: we have what we're seeing, and nothing more.
Where is it on the roadmap, as it doesn't seems to fit anywhere? Again, the simplest explanation would be: this lens is not on the K-mount roadmap.
The lens is a limited mock up of some sort. It is difficult to tell a lot of things about it from a single pic. However, your simplest explanation does nothing to explain how a lens can operate with a k-mount at 2 different registration distances. You finally admit the Road Map is just a plan and isn't 100% guarantee.

QuoteOriginally posted by Kunzite Quote
There are 3 questions you should ask yourself:
- does it really make sense to have a nice focus ring, but zoom by twisting the barrel itself?
Makes as much sense as a skinny focus ring when going manual focus.
QuoteOriginally posted by Kunzite Quote
- where is the collapsing/extending mechanism? How is it operated, how about barrel travel - since the lens is so short?
The Mechanism would be internal. It would be short when collapsed. Plus, the focus & zoom could be a one touch design.
QuoteOriginally posted by Kunzite Quote
- does it make sense to have a collapsible wide prime? Taking the picture as a reference, you'd have the barrel extends (with the lens set to infinity) by as much as the protrusion, maybe more. It would easily be longer than the 70mm (which is remarkably short, without the lens hood)
It would make sense if they were trying to keep the K-01 and successors close to pocketable when not in use. That is the same concept behind the Oly 14-42mm, Pany 14-42mm X and the old Leica 50mm collapsible lenses on the rangefinders.

Now ask yourself 2 questions that you keep avoiding. 1) What is the purpose of the rear element of the prototype in the pic so deep inside the body? 2) How does this effect the registration distance?

Remember, the registration distance of the k-01 and K-5 and every dSLR every made by Pentax (or Asahi Optical) is 45.46 mm. Sure they could change it. However, if this lens has a different registration distance, it will not work on the K-01 OR any other dSLR by Pentax. This prototype has the k-mount flange. Like I have said half a dozen times, it is just a guess.

Last edited by Blue; 05-06-2012 at 04:25 PM.
04-25-2012, 10:07 AM   #70
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MS optics (sonnetar) makes a collapsible triplet for the leica that sits flat on the camera but extends out for use. this could be part of the design (though given the target of K-01 users the extension better be automatic when the camera is powered on )

the perar is below



04-25-2012, 10:22 AM   #71
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This prototype has a barrel more like the DA 21 and DA 40 LTD than the 15m or 70. The infinity mark and distance scale match up with the DA 40 when in the infinity position. However, the barrel looks like the DA 40 when extended the most for the closest focus. However, the front element is a lot larger than the 21 or the 40mm as well as the 15 and 70mm. It has threads for a filter or hood like the DA 40 ltd rather than the bayonet style of the 21. The protruding rear element is the biggest mystery.


04-25-2012, 10:24 AM   #72
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QuoteOriginally posted by eddie1960 Quote
MS optics (sonnetar) makes a collapsible triplet for the leica that sits flat on the camera but extends out for use. this could be part of the design (though given the target of K-01 users the extension better be automatic when the camera is powered on )

the perar is below


Even more so for entry level dSLR users because the mirror would smack the thing. :Hysterical: My m4/3 bodies (ep-1 and GF) tell me to check the lens status when it is collapsed and it won't work other wise. The new Panny collapsible does automatically extend and collapse with power on and off.
04-25-2012, 10:34 AM   #73
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Blue:
IMO it's quite easy to figure out some things from that single pic.
Operating at 2 different registration distances? That would not be the case, the registration distance being the same (standard for K-mount). What is different from a "true" K-mount lens is the significantly smaller mirror clearance (not enough even for APS-C, it seems).
The Roadmap not being 100% guaranteed - you sent me PMs asking to drop the issue, then coming up with this silly strawman? Btw, it's not in the K-mount roadmap, most likely, because it's not a "true" K-mount lens. MHO.

About your answers:
- focus rings like that are on other lenses, and they're pretty much usable. You haven't answered the question, though.
- in the picture the lens is presumably collapsed. The barrel would have to extend some distance (to un-collapse), then even more to focus. If it's a zoom, guess what... Quite difficult to do in a such short lens.
- those are zooms, of a different construction; I can see from a mile they're collapsible. OTOH, I believe it makes much more sense to have compact primes, instead of bigger, collapsible ones.

Unlike you, I don't avoid questions. Here we go:
1) It allows using a less retrofocus design for wide angle lenses
2) It doesn't.

The front element is not "a lot larger" than the 70mm's; it looks more or less the same.

eddie1960, different lens, different mechanisms...
04-25-2012, 11:01 AM   #74
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QuoteOriginally posted by Kunzite Quote
Blue:
I
The front element is not "a lot larger" than the 70mm's; it looks more or less the same.
Not that it matters because the front elements of the 21 ltd and 40 ltd are small. Rough comparison of the mystery DA ltd prototype and DA 70 ltd.










QuoteOriginally posted by Kunzite Quote
eddie1960, different lens, different mechanisms...
Exactly. This new lens is different lens.

Edit: If the registration distance is the same, why the protruding rear element?

Last edited by Blue; 04-25-2012 at 12:19 PM.
04-25-2012, 11:26 AM   #75
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Elements look just about the same size to me (if the bodies were scaled properly).
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