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02-10-2012, 07:45 AM   #46
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QuoteOriginally posted by deadwolfbones Quote
Getting pretty tired of this "common knowledge" that 60mm is a useless focal length. I loved using the DA 40 on my K-7 and K-5, and I love using the FA 43 on it now (probably my favorite Limited overall). Tastes differ in focal lengths as in all other things. Every focal length is useful for something.
QuoteOriginally posted by Zygonyx Quote
Exactly.
Seems odd to always hear the same conventional dogms...
Personally, I've found 40mm much more useful on APS-C than 50mm. 50mm is no man's land for me - too long indoors and too short outdoors.

02-10-2012, 07:48 AM   #47
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QuoteOriginally posted by Docrwm Quote
DUH, you were completely unclear in your post - D-U-H
I stated I was talking about the 40 XS and Pentax indicated it was compatible with dSLR bodies. Why do YOU think any future XS would not be? Why would its mount be different than the 40 XS? I don't find a dozen fellows sitting around the bar drinking beer pontificating an official response from Pentax on the matter. All I was saying is that an official statement from Pentax Japan is lacking on the matter. I made a suggestion that Ole or Adam ask them in the interview tomorrow.
02-10-2012, 08:25 AM   #48
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QuoteOriginally posted by MSM Quote
I agree. I actually was wondering if this is a mock up of the DA Limited zoom. Perhaps they have used the barrel of the 40 mm in the prototype. As you note, this is not finalized. The actual lens may be slightly larger with a zoom ring. This way Pentax can show a little without showing it all. They let you know it is the limited by the casing and show off the rear portion of the lens to show off the concept of how they plan on keeping the future lenses smaller. If true, I would guess that the portion extending out back would not be so great. Instead the barrel could be bigger to allow for the zoom ring. Just my dreaming... but if I am right I am calling it first! otherwise forget what I said. My only speculative support is the fact that the lens map shows a da limited zoom but no prime scheduled. Also, others are claiming that from the front element it looks like a wide angle lens. It is an exciting time to be a Pentaxian!
the da zoom made with the K-01 in mind actually makes a ton of sense (and as much as I am a prime guy a K-01 wit a small pancake zoom could be a pretty ideal "little" camera no more sitting the 18-55 on it and making it look huge compared to a nex with 18-55. It's also what will be needed for the mass market P&S upgraders who definitely are not looking for a prime lens solution
02-10-2012, 08:30 AM   #49
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QuoteOriginally posted by johnmflores Quote
Personally, I've found 40mm much more useful on APS-C than 50mm. 50mm is no man's land for me - too long indoors and too short outdoors.
it's not a bad length. my first camera with a with a 58 f2 and for a long time that was the only lens i had (paired after a few months with a 2 x converter and much later a 28 and a 135 - my first zoom was probably not until the late 80's actually and the first one i used regularly was my 28-200 i got with the mz5n ) I managed quite well with the length only occasionally looking for a wider lens (I was a lot younger though so lots of walking to zoom out with my feet wasn't as much of an issue )

02-10-2012, 08:36 AM   #50
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QuoteOriginally posted by eddie1960 Quote
the da zoom made with the K-01 in mind actually makes a ton of sense (and as much as I am a prime guy a K-01 wit a small pancake zoom could be a pretty ideal "little" camera no more sitting the 18-55 on it and making it look huge compared to a nex with 18-55. It's also what will be needed for the mass market P&S upgraders who definitely are not looking for a prime lens solution
A collapsible zoom would be excellent, especially if it is in the spirit of the LTD lenses. However, they have never released a LTD zoom (as suggested by MSM). It would be a first. However, if it were compatible with the K-01 and dSLR, that would be a plus.
02-10-2012, 08:50 AM   #51
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QuoteOriginally posted by johnmflores Quote
Personally, I've found 40mm much more useful on APS-C than 50mm. 50mm is no man's land for me - too long indoors and too short outdoors.
40-45mm on 135 was long considered the ideal length for RF optics, said to most closely resemble our "normal" FOV.

40mm on APS-C adds some compression which is, dare I say, more "photographic" in that it is artificially constructed through optics.

...or, 40mm is the new 58mm!
02-10-2012, 10:51 AM   #52
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'Normal' has many meanings. 'Norma' is Latin for a carpenter's square, so 'normal' means "at right angles". In optics, 'normal' is the frame diagonal. In statistics, 'normal' means a value within a certain proximity to an average. In common usage, 'normal' means either "not too weird" or "what we're used to". Et cetera.

For 135/FF frames, optical-normal is 43mm. Many 135 RFs had lenses around 40-45mm -- a few stare down at me from my shelves. Lensmakers found the 50-60mm range more suitable|producible for SLRs. Many SLR shooters became used to that range, so Fifties were a de-facto 'normal'. But many users of RFs such as the Olympus XA became used to its 35mm lens -- it's 'normal' on that camera for those users. So we have 135/FF psychological-normal ranging from 35-60mm. Whew! And APS-C 'normal' may range from 24-43mm, again depending on our psycho-visual canalization.

What we're used to. What we're comfortable with. How we limit our vision. All these are related to 'normal' camera usage. That's one reason for my LOTD (lens of the day) strategy, where I semi-randomly choose a lens to use for a day or ten, to train my visual system to that FOV. For even more fun, I'll use a cheap safe wide-flange NIF (no infinity focus) M42-PK adapter and/or thin macro tube to pull-in the focus range. This forces me to not only seek subjects within a specific FOV, but also in a more limited zone. Yes, it's great eye-training.

ObTopic: If Kowa is making lenses for Q, who might make XS-specific lenses?

Last edited by RioRico; 02-10-2012 at 11:11 AM.
02-10-2012, 03:10 PM   #53
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QuoteOriginally posted by Douglas_of_Sweden Quote
Here is a possible solution for how they may have solved this in a safe way. Let us assume that the lens elements are recessed enough into the mirror-box enough to interfere with the mirror when it moves, but not when it just sit there. You could then mount the lens with no problems. The camera could then simply refuse to fire because the camera will know that it is a recesses lens when it identifies the lens. That could be applied on all following DSLRs, and it could be applied with software upgrades on previous DSLRs. For what I know there may even already exist a code that the lens could send to prevent firing even with existing in-camera-software (though it would take a lot of hindsight). Problem remain with film SLRs, but not many people mount any DA lenses on film bodies.
But I think it is more likely that you will just get a warning note in the lens-box when you buy a lens with recesses lens elements.
The above sounds like a good idea to me, but how about this:

Assuming the rear element is long enough that it bumps up onto the mirror. Pentax could add a pin that prevents mounting on older cameras. The lens mounts fine on the K-01, as there is nothing in the way of the pin. However, on all future DSLRs Pentax could make it so the pin pushes into a mechanism that physically pushes the mirror up. Kind of like a mirror lock up button triggered by a pin. When you insert a K-01 lens e.g. into a K-3 body the mirror automatically flips out of the way (even when the camera is off) and you can only use live view mode for taking pictures.

How does that sound? Plausible solution?

02-10-2012, 04:05 PM   #54
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Very inventive. I like it, as long as it doesn't turn into another Ricoh pin...
02-10-2012, 04:58 PM   #55
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QuoteOriginally posted by jms698 Quote
How does that sound? Plausible solution?
The lens is already as deep into the body as it is going to go before you can start to twist it to lock it into place. Unfortunately if the lens is deep enough to interfere while shooting it will be deep enough to interfere while mounting.
02-10-2012, 05:42 PM   #56
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QuoteOriginally posted by RXrenesis8 Quote
The lens is already as deep into the body as it is going to go before you can start to twist it to lock it into place. Unfortunately if the lens is deep enough to interfere while shooting it will be deep enough to interfere while mounting.
You could gain a couple of millimeters if you enlarged the tabs on the lens so that you cannot place the 'new' lens into the 'old' body; in other words, the lens would never be able to get 'deep' enough for you to start twisting it.

If you made some 'extra thick' tabs on the lens in some odd location you could conceivably gain a few more millimeters, but at that point I'd just prefer they let us smash the mirror if we're being stupid.
02-10-2012, 08:52 PM   #57
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QuoteOriginally posted by ElJamoquio Quote
You could gain a couple of millimeters if you enlarged the tabs on the lens so that you cannot place the 'new' lens into the 'old' body
Well, then it wouldn't work with the K-01 which has the same KAF2 mount as current pentax DSLR's!



02-21-2012, 03:55 PM - 1 Like   #58
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QuoteOriginally posted by RXrenesis8 Quote
Well, then it wouldn't work with the K-01 which has the same KAF2 mount as current pentax DSLR's!




Mmh, actually, it doesn't look the same.
Compare the outer diameter of the mount!
It is smaller on the K-01.
So if they equip the lens with an edge around the bayonet that fit tight around the bayonet on the K-01...you won't be able to mount the lens on the K-5 or other K mount DSLR/SLRs!
02-21-2012, 04:16 PM   #59
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Good catch.
02-21-2012, 04:29 PM   #60
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QuoteOriginally posted by Douglas_of_Sweden Quote
Mmh, actually, it doesn't look the same.
Compare the outer diameter of the mount!
It is smaller on the K-01.
So if they equip the lens with an edge around the bayonet that fit tight around the bayonet on the K-01...you won't be able to mount the lens on the K-5 or other K mount DSLR/SLRs!
If that works (i.e. the mechanical obstruction is sufficient to keep the lens from touching the mirror) then I am gratified - and my earlier posts will be justified.

Make some GREAT lenses and we have another reason to purchase a K-01.
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