[Blue]

Blue, you should stop and try to understand things like "registration distance" and "retrofocus" instead of arguing. Currently, you don't.

That isn't the issue.

A K-01 like camera is a mirrorless camera with a K-mount, i.e. the same registration distance. It's easy to understand such a lens, if you know the basics:
a. the K-mount is kept for compatibility reasons (all K-mount lenses can be used directly). . . . .

Wow. You think?

Even your insistence that old retrofocus K-mount lenses does not protrude into the mount shows your lack of understanding. Of course they don't, since they were specifically designed to leave enough room for the moving SLR mirror (mirror clearance). That's what the retrofocus design does.

I never said it it didn't protrude, I said they designed retrofocus lenses such as the Auto-Tak 35/2.3 that still cleared the mirror at infinity focus. I actually have one of these lenses which was released 1 year before the Nikkor slr retrofocus 35/2.8.

---

Last edited by Blue; 04-25-2012 at 05:19 PM. Reason: tone

[Blue]

If they are going with a single focal length limited with such a radical retrofocus, perhaps it is wider than the DA 15 ltd. Too bad such a lens would be relegated to the k-01 only. However, the distance scale doesn't make sense if that is the case unless they just used one from the parts bin for the prototype.

[eddie1960]

it's not retro focus it's a biogon type design (look at the biogon lenses from zeiss many protrude into the camera body but the registration distance is still the same. the Russian jupiter 12 i posted a pic of is an LTM variant of this design (which dates to 1935), but the same lens exists in Contax mount as well, and Lieca M mount as a proper biogon if i'm not mistaken

the voigtlander 12 and 15 mm are ff lenses that do the same in leica M mount
the mount registration distance is the same, nothing to do with wher the rear of the lens can be aside from the mirror in an SLR. many rangefinder designs protrude though

I confused the issue mentioning retrofocus , it's a non-retrofocus design which couldn't be used with a mirror but an RF or view camera or mirrorless would have no issues with such a design (given the biogons go back to well before SLR that is no surprise)

[Mareket]

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

To allow for non-retro focus wide angle designs. I'm sure this has been made clear a fair number of times by now. I can't remember the specifics, but moving the rear point closer allows more control over optical quality because the ray paths can't diverge as much after they leave the glass because they don't have to travel as far. Something like that.

They're utilising the extra space in the "mirror" box of the K-01 to give it a USP. An SLR form factor and mount but the ability to use non-retro-focus wide angles and more compact lenses and such. I'd have thought this was pretty obvious...

They wouldn't change the registration distance.

[Kunzite]

:BS:

That's an accurate description of your recent posts. Too bad you refuse to take a step back and learn something, instead of aggressively pursuing the same ideas.

I don't just think, I know - the K-01 is the camera that proves it. But maybe a real product is not proof enough for you...

Talking about "such radical retrofocus" when allowing the lens to protrude inside the mount means a milder retrofocus design? (for a 15mm, they can't make a non-retrofocus) Again: try to understand the basics before arguing.

There is nothing wrong with the distance scale; you're mistakenly assume that it should match one lens or another. It shouldn't.

[Blue]

That's an accurate description of your recent posts. Too bad you refuse to take a step back and learn something, instead of aggressively pursuing the same ideas.

I don't just think, I know - the K-01 is the camera that proves it. But maybe a real product is not proof enough for you...

Talking about "such radical retrofocus" when allowing the lens to protrude inside the mount means a milder retrofocus design? (for a 15mm, they can't make a non-retrofocus) Again: try to understand the basics before arguing.

There is nothing wrong with the distance scale; you're mistakenly assume that it should match one lens or another. It shouldn't.

Disengage with me on this.

[Kunzite]

Still refusing to learn?

Look what I've found after a very brief google search (I haven't fully read it, however at a quick glance it looks OK):
http://www.rogerandfrances.com/photoschool/ps%20basics%20lens%20design.html

[Blue]

To allow for non-retro focus wide angle designs. I'm sure this has been made clear a fair number of times by now. I can't remember the specifics, but moving the rear point closer allows more control over optical quality because the ray paths can't diverge as much after they leave the glass because they don't have to travel as far. Something like that.

If this is in fact a range finder type lens, it makes sense for a wide angle.

They're utilising the extra space in the "mirror" box of the K-01 to give it a USP. An SLR form factor and mount but the ability to use non-retro-focus wide angles and more compact lenses and such.

However, it will be a disappointment to a lot of people that there will be DA LTD lens that won't work on k-mount dSLR bodies. It would limit the market.

I'd have thought this was pretty obvious...

What? From a single unmarked mystery LTD lens picture? If you notice, the distance markings are approximately where they would be for a ~ 28mm lens as well as the 40 ltd.

They wouldn't change the registration distance.

That is what I have been saying.

[gazonk]

However, it will be a disappointment to a lot of people that there will be DA LTD lens that won't work on k-mount dSLR bodies. It would limit the market.

Finally a limited that deserves its name!

[Mareket]

However, it will be a disappointment to a lot of people that there will be DA LTD lens that won't work on k-mount dSLR bodies. It would limit the market.

It'd be more of a shame to introduce a new camera with the room to utilise inside and then ignoring the possibilities to retain backwards compatibility. It's not like the K-mount is short of good quality prime lenses anyway. The K-01 needs to flex it's muscles and show that it has specific advantages that can be utilised in terms of lens design, it's be ridiculous to ignore that.

What? From a single unmarked mystery LTD lens picture? If you notice, the distance markings are approximately where they would be for a ~ 28mm lens as well as the 40 ltd.

Yeah, from a single unmarked mystery LTD lens picture, with XS designation. But the focal length worries me, because the markings do match the 40mm very well. It's obviously not another 40mm lens, but it'll be around there, and I really think a 28/35mm equivalent or something would have been a much better idea. If it is a 28mm, which it well could be, then I guess that'd be ok.

We shall have to wait and see...

[Kunzite]

Blue's really going full retard in here today.

Wow, he's now guessing the focal length based on the distance scale...

Blue, FFS, if it were a rangefinder(mirrorless)-mount lens the protrusion would hit the sensor/film.

Mareket, I'd say it's wider - under 30mm, possibly much less. I can't know, but it seems to be a significantly retrofocus design... or maybe a faster lens?
Markings tells us nothing.

[Blue]

It'd be more of a shame to introduce a new camera with the room to utilise inside and then ignoring the possibilities to retain backwards compatibility. It's not like the K-mount is short of good quality prime lenses anyway. The K-01 needs to flex it's muscles and show that it has specific advantages that can be utilised in terms of lens design, it's be ridiculous to ignore that.



Yeah, from a single unmarked mystery LTD lens picture, with XS designation. But the focal length worries me, because the markings do match the 40mm very well. It's obviously not another 40mm lens, but it'll be around there, and I really think a 28/35mm equivalent or something would have been a much better idea. If it is a 28mm, which it well could be, then I guess that'd be ok.

We shall have to wait and see...

A very fast 28mm would makes sense. It would be close to the sensor diagonal of the K-01 and potential successors and would be kind of like a normal prime for the genre.

Edit: From these images, a collapsible zoom seems ruled out but there is a groove in the black base. That means it is "off" the Road Map. A 3rd 40mm or 4th 35mm would be "wild."

[ChopperCharles]

The 40mm XS has me very excited, because it is within my price range. I never considered the other 40mm pancake before now because the price was simply too high. But $250 I can deal with, it's the next on my list.

Charles.

[DaveHolmes]

Makes me wonder if next week we'll see the official announcement of the next two Q lenses (04 & o5) as well as something new for the K-mount...

Was there ever actually an anouncement or has this thread just been anothe 'hype-fest' speculation exercise for massive geeks with too much time on their hands (myself included)?

[eddie1960]

Was there ever actually an anouncement or has this thread just been anothe 'hype-fest' speculation exercise for massive geeks with too much time on their hands (myself included)?

we haven't reached next week yet, 7 pages in 4 days