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Metabones Speed Booster for Pentax K lenses?

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KentG said:
KentG wrote:

You are missing the entire point of the adapter. There are less Pentax users on the planet than Canon and Nikon by a large margin. Its not the number of lenses available but the number of users available to buy it. They probably did a demographic study pinpointing how many NEX users had both a NEX and a DSLR system and which one. Also what kind of lenses NEX owners would like to be able to mount. And I am betting that in Europe Contax, Zeiss and Alpa were on the radar due the the high overall quality of their lenses (I was an Alpa shooter once upon a time).

They are not looking to sell these to people who would go out and buy a certain brand of lens to mount, but instead to people who already have the brand of lens they want to mount.

Kent Gittings
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Kent for my "two bob" I still think that the aperture lever out the back is a problem. Also the Canon EF version actually "talks" to the Sony NEX body. Perhaps it might be possible to fiddle with a MF PK mount but an autofocus PK lens might be in the hands of the firmware boffins to sort out.

(no relation)

--
Tom Caldwell
 
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Ari Aikomus said:
Ari Aikomus wrote:
Ari Aikomus said:
ET2 wrote:
Ari Aikomus said:
KentG wrote:

You are missing the entire point of the adapter. There are less Pentax users on the planet than Canon and Nikon by a large margin.
Click to expand...
Besides, the Nikon version should be able to use Pentax lenses anyway with K mount to F mount adapter..

http://www.amazon.com/Fotodiox-Mount-Adapter-Pentax-Camera/dp/B003Y31A2W
Click to expand...
You both are missing the point.

ET2...This Pentax-Nikon adapter use correction glass. Not a good thing - at all, especially with speedbooster!
Click to expand...
You can pick a speedbooster adapter that doesn't use correction glass. You need a mount version that has smaller flange than the K-mount
 
Tom Caldwell said:
Tom Caldwell wrote:
Tom Caldwell said:
No idea then. I would wager that there are more Pentax M42 and K mount available than ALPA, Contarex or Contax lenses combined, so you would think there is a reasonable business case to make a Pentax adapter.
Click to expand...
Dumb M42 to EF adapter works fine on the Speed Booster.
Click to expand...
not necessarily:

Some improperly-made M42 screw mount adapters may short the electronic contacts of the Speed Booster™ and cause damage to the Speed Booster™ and/or camera body.

http://www.metabones.com/sony/ef-e-speed-booster

An why buy 600$ EF->NEX adapter, if you haven't EF lenses, just manual m42?

Ari




 
Tom Caldwell said:
Tom Caldwell wrote:
Tom Caldwell said:
KentG wrote:

You are missing the entire point of the adapter. There are less Pentax users on the planet than Canon and Nikon by a large margin. Its not the number of lenses available but the number of users available to buy it. They probably did a demographic study pinpointing how many NEX users had both a NEX and a DSLR system and which one. Also what kind of lenses NEX owners would like to be able to mount. And I am betting that in Europe Contax, Zeiss and Alpa were on the radar due the the high overall quality of their lenses (I was an Alpa shooter once upon a time).

They are not looking to sell these to people who would go out and buy a certain brand of lens to mount, but instead to people who already have the brand of lens they want to mount.

Kent Gittings
Click to expand...
Kent for my "two bob" I still think that the aperture lever out the back is a problem. Also the Canon EF version actually "talks" to the Sony NEX body. Perhaps it might be possible to fiddle with a MF PK mount but an autofocus PK lens might be in the hands of the firmware boffins to sort out.

(no relation)
Click to expand...
C/Y lenses also have same kind of lever than Pentax K lenses, but C/Y->NEX speedbooster adapter exist.

I don't know how hard it is to make the Penatx K AF version, but the a dumb version would not be difficult at all. And it would be cheaper, such as C/Y-> NEX version - 400$



http://www.metabones.com/buy-speed-booster/contax-yashica-lens-to-sony-nex-speed-booster-detail



Ari
 
MightyMike said:
MightyMike wrote:

Tape should solve the problem of shorting contracts
Click to expand...


Yep,. Tape is excellent solution for 600$ speedbooster ;)

You can use m42 lenses easier with 400$ C/Y-speedbooster.

The same optical quality.


 
ET2 said:
ET2 wrote:
ET2 said:
Ari Aikomus wrote:
ET2 said:
ET2 wrote:
ET2 said:
KentG wrote:

You are missing the entire point of the adapter. There are less Pentax users on the planet than Canon and Nikon by a large margin.
Click to expand...
Besides, the Nikon version should be able to use Pentax lenses anyway with K mount to F mount adapter..

http://www.amazon.com/Fotodiox-Mount-Adapter-Pentax-Camera/dp/B003Y31A2W
Click to expand...
You both are missing the point.

ET2...This Pentax-Nikon adapter use correction glass. Not a good thing - at all, especially with speedbooster!
Click to expand...
You can pick a speedbooster adapter that doesn't use correction glass.
Click to expand...
No, you can't! Do you even know what we are talking about here? Do you know what is Metabones Speedbooster?

It has always lens elements inside adapter:

http://www.metabones.com/info/105-info/154-speed-booster
ET2 said:
You need a mount version that has smaller flange than the K-mount
Click to expand...
Really?! lol...I think you should stay just as loud Sony fanboy. Suits may be better for you, than the cameraexpert role.

Besides, the subject was: Why no Speedbooster for Pentax K lenses yet...



Ari





--
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'
 
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Ari Aikomus said:
Ari Aikomus wrote:
Ari Aikomus said:
ET2 wrote:
Ari Aikomus said:
Ari Aikomus wrote:
Ari Aikomus said:
ET2 wrote:
Ari Aikomus said:
KentG wrote:

You are missing the entire point of the adapter. There are less Pentax users on the planet than Canon and Nikon by a large margin.
Click to expand...
Besides, the Nikon version should be able to use Pentax lenses anyway with K mount to F mount adapter..

http://www.amazon.com/Fotodiox-Mount-Adapter-Pentax-Camera/dp/B003Y31A2W
Click to expand...
You both are missing the point.

ET2...This Pentax-Nikon adapter use correction glass. Not a good thing - at all, especially with speedbooster!
Click to expand...
You can pick a speedbooster adapter that doesn't use correction glass.
Click to expand...
No, you can't! Do you even know what we are talking about here? Do you know what is Metabones Speedbooster?
Click to expand...
Given I knew about Speedbooster long before you even heard of the name, and long before DPR posted about it on this site, I would say yes I have heard about speedbooster.

And by the way, the electronic contact part of speedbooster that allows Nex cameras to electronically control aperture on Canon lenses was designed by conurus, and I was on their forums long before they licensed that chip to Metabones.

So yes I would say I know more than you ..
Ari Aikomus said:
Ari Aikomus said:
You need a mount version that has smaller flange than the K-mount
Click to expand...
Really?! lol...I think you should stay just as loud Sony fanboy. Suits may be better for you, than the cameraexpert role
Click to expand...
I suggest you watch your tone and show some respect, especially if you don't have reading comprehension to understand what I said.

Let me repeat once again: A mount that has smaller flange distance than the K-mount won't require a glass element --- here I am not talking about SpeedBooster. You need to find a SpeedBooster version (I am assuming you are planning to use it with Nex/Fuji cameras) where the mount has smaller flange distance than the K-mount. Then you can mount another (glassless adapter) on top of Speedboster (which has glass, I know, genius) and use Pentax lenses.

It's a stack of two adapters. One Speedbooster and another one on top that is glassless.
 
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Ari Aikomus said:
Ari Aikomus wrote:

Besides, the subject was: Why no Speedbooster for Pentax K lenses yet...
Click to expand...
Yeah, and we gave you an answer. No market for it, and someone who really really needs it can easily adapt any other SpeedBooster where the original mount (for example Canon) has smaller flange than the K-mount. All you will then need is another glassless K-mount adapter on top without any image quality comprise, as that second adapter on top would be glassless.
 
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Yes! We will consider for this….

(speedbooster for Pentax K lenses)



So there is some hope...



cheers,



Ari
 
steephill said:
steephill wrote:

http://www.dpreview.com/news/2013/0...ed-booster-lens-adapter-for-micro-four-thirds So even if they decide to try a K mount version it would be a long way back in the queue. There might even be a Pentax FF by then :)
Click to expand...
We're talking about different things now. I don't ask speedbooster for pentax mount camera (it is impossible because flange distance), BUT I ask speedbooster for Pentax K lenses. For example PK->NEX speedbooster!

We have already Contax/Yashica-NEX speedbooster, Pentax-lens version would be very easy to design, because contax/yashica mount is quite similar with Pentax-K mount, even flange distance is same: 45.5mm.

Speedbooster for mirrorless m43 is an entirely different story, requires more work.



cheers,



Ari



 
ET2 said:
ET2 wrote:
ET2 said:
Ari Aikomus wrote:

Besides, the subject was: Why no Speedbooster for Pentax K lenses yet...
Click to expand...
Yeah, and we gave you an answer.
Click to expand...
sorry, but you did not give me anything other than false information.
ET2 said:
No market for it,
Click to expand...
You don't know that. I don't know either for sure, but I think that it would be more market to the Pentax K lenses speedbooster than for Contax/Yashica lenses!

ET2 said:
and someone who really really needs it can easily adapt any other SpeedBooster where the original mount (for example Canon) has smaller flange than the K-mount. All you will then need is another glassless K-mount adapter on top without any image quality comprise, as that second adapter on top would be glassless.
Click to expand...
Again BS. Learn your lesson before giving instructions.



You don't know that aperture lever of Pentax K lenses may hit the adapter when you try mount Pentax K lens with EOS adapter to the speedbooster?

http://www.metabones.com/sony/ef-e-speed-booster



Many manual focus lenses (e.g. OM 28/2.8, OM 50/1.8, Leica R 15/3.5) have rear protrusions (spikes, levers, other appendages) which would damage the optics and/or housing of Speed Booster™. They need to be modified before they can be safely used on Speed Booster™. Check and make sure there are no rear protrusions from the adapter/lens combination before using on Speed Booster.
 
Ari Aikomus said:
Ari Aikomus wrote:
Ari Aikomus said:
steephill wrote:

http://www.dpreview.com/news/2013/0...ed-booster-lens-adapter-for-micro-four-thirds So even if they decide to try a K mount version it would be a long way back in the queue. There might even be a Pentax FF by then :)
Click to expand...
We're talking about different things now. I don't ask speedbooster for pentax mount camera (it is impossible because flange distance), BUT I ask speedbooster for Pentax K lenses. For example PK->NEX speedbooster!

We have already Contax/Yashica-NEX speedbooster, Pentax-lens version would be very easy to design, because contax/yashica mount is quite similar with Pentax-K mount, even flange distance is same: 45.5mm.

Speedbooster for mirrorless m43 is an entirely different story, requires more work.

cheers,

Ari
Click to expand...
 
They have a full work schedule which is already falling behind by many months so any additional models such as your desired K-NEX model will take a long time to deliver. So long in fact that anyone who wants to get full use of Pentax FF lenses will probably have a suitable Pentax FF body available to them to achieve this without the use of adaptors. The gain in aperture with an APS-C body/adaptor combo will be negated by the better performance of a FF sensor.

As an aside note the registration distance of C/Y is not the same as K, nearly, but not quite. The difference is enough to frustrate infinity focus when mounting C/Y lenses on K bodies. The Leitax mounts correct this of course.
 
steephill said:
steephill wrote:

They have a full work schedule which is already falling behind by many months so any additional models such as your desired K-NEX model will take a long time to deliver. So long in fact that anyone who wants to get full use of Pentax FF lenses will probably have a suitable Pentax FF body available to them to achieve this without the use of adaptors. The gain in aperture with an APS-C body/adaptor combo will be negated by the better performance of a FF sensor.
Click to expand...
Yep, but this was not the point of this thread...


steephill said:
As an aside note the registration distance of C/Y is not the same as K, nearly, but not quite. The difference is enough to frustrate infinity focus when mounting C/Y lenses on K bodies.
Click to expand...
Hardly a problem:

Infinity adjustment



furthermore:
steephill said:
The Leitax mounts correct this of course.
Click to expand...
And of course metabones will use proper K-mount bayonet plate (correct PK flange distance) with their PK-lens speedbooster!

I'll admit that speedbooster for Pentax K AF lenses would be very difficult (if not impossible) to implement, BUT on the other hand, the simpler - manual - adapter should be very easy to do! And would make many of us happy. That's a point that Metabones has lost - so far ...



Ari
 
Disclosure: we have a business relationship with Metabones. On one hand I am an "insider" and on the other hand please take note my viewpoints are likely biased because of this relationship.

I did personally tested Pentax K mount lenses fitment and sent them the dimension data to support K mount lenses (including making sure the very long aperture lever doesn't get in the way). There is in principle no problem whatsoever making a Pentax K lens Speed Booster, and they are looking into it.

Perceived lack of demand is not an issue for a company that support Alpa on day one. That is not the reason why there is no Pentax K at this point.

Please note that a "no" is not necessarily a hard "no" forever. As some of you have observed, there is already a long pipeline pending, including m4/3 camera bodies, and on the lens side we have yet to see Nikon F/G, Canon FD, Minolta MD and Rollei QBM. Don't get me wrong, Pentax K is every bit as important as any of the aforementioned, it is just that instead of making further promises, they have (IMHO) correctly chosen to deliver on their existing commitments first. A steady stream of new mounts are trickling out and we have already seen Contax/Yashica and Contarex. There is no inherent difficulty other than the sheer number of so many combinations of mounts to support.

The Pentax K lens must have a physical aperture ring, however. FA J and DA lenses shall not be supported in any event. This way the pricing will likely be $399 instead of $449 and it will be out in the market more quickly. Most J/DA lenses do not cover FF, anyway, so I hope this would not be an unacceptable impediment.
 
Ari Aikomus said:
Ari Aikomus wrote:

Again BS. Learn your lesson before giving instructions.

You don't know that aperture lever of Pentax K lenses may hit the adapter when you try mount Pentax K lens with EOS adapter to the
Click to expand...
Good thing you added the word "may". Buy the secondary K-mount adapter where the aperture lever may not hit the the optics.

What I said still stands. There is no logical reason why you should not be able to stack two adapters, one Speedbooster and another one on top that is glassless. All you need is Speedbooster adapter that has smaller flange distance than the K-mount.

What about Contarex Lens Speedbooster? What's the flange distance on that mount? If it's smaller than Canon, that should be plenty of space on top for K-mount glassless adapter.
 
I'm so glad your encouraging message ;)


cyberstudio said:
cyberstudio wrote:

Disclosure: we have a business relationship with Metabones. On one hand I am an "insider" and on the other hand please take note my viewpoints are likely biased because of this relationship.

I did personally tested Pentax K mount lenses fitment and sent them the dimension data to support K mount lenses (including making sure the very long aperture lever doesn't get in the way). There is in principle no problem whatsoever making a Pentax K lens Speed Booster, and they are looking into it.

Perceived lack of demand is not an issue for a company that support Alpa on day one. That is not the reason why there is no Pentax K at this point.
Click to expand...
OK...


cyberstudio said:
Please note that a "no" is not necessarily a hard "no" forever. As some of you have observed, there is already a long pipeline pending, including m4/3 camera bodies, and on the lens side we have yet to see Nikon F/G, Canon FD, Minolta MD and Rollei QBM. Don't get me wrong, Pentax K is every bit as important as any of the aforementioned, it is just that instead of making further promises, they have (IMHO) correctly chosen to deliver on their existing commitments first. A steady stream of new mounts are trickling out and we have already seen Contax/Yashica and Contarex. There is no inherent difficulty other than the sheer number of so many combinations of mounts to support.

The Pentax K lens must have a physical aperture ring, however. FA J and DA lenses shall not be supported in any event.
Click to expand...
This sounds reasonable, but please note that there already are simple Pentax FA J and DA TO NEX adapters ...

Pentax DA to NEX



...With Lock Open Switch to control the aperture of the DA lens!

This kind of simple mechanics could work also with Pentax K -> NEX speedbooster!









cyberstudio said:
This way the pricing will likely be $399 instead of $449 and it will be out in the market more quickly. Most J/DA lenses do not cover FF, anyway, so I hope this would not be an unacceptable impediment.
Click to expand...
 
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