Metabones Speed Booster for Pentax K lenses?

Started Apr 14, 2013 | Discussions
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Ari Aikomus
Ari Aikomus Veteran Member • Posts: 7,717
Metabones Speed Booster for Pentax K lenses?

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

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BobORama
BobORama Senior Member • Posts: 2,195
Re: Metabones Speed Booster for Pentax K lenses?
1

WHY would you want to use a product that reduces contrast and increases CA, when Instagram is free?

 BobORama's gear list:BobORama's gear list
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MightyMike Forum Pro • Posts: 35,699
Re: Metabones Speed Booster for Pentax K lenses?
2

Mathematically it should actually increase the contrast, as for the CA that depends on the parent lens and speedbooster combination but in many cases it could reduce the CA

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Ayoh Regular Member • Posts: 210
Re: Metabones Speed Booster for Pentax K lenses?

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
No speedbooster for Pentax lenses ;(...

Ayoh wrote:

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

I wrote Metabones to enquire about a Pentax K to NEX adapter and this is the response:

Sorry! We have not planning to make a Pentax (speed booster)…..
Thank you!
Alex
GBI Ltd

Do not get them. There's a lot of Pentax K FF lenses on the planet...

Ari

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Ayoh Regular Member • Posts: 210
Re: No speedbooster for Pentax lenses ;(...

Ari Aikomus wrote:

Ayoh wrote:

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

I wrote Metabones to enquire about a Pentax K to NEX adapter and this is the response:

Sorry! We have not planning to make a Pentax (speed booster)…..
Thank you!
Alex
GBI Ltd

Do not get them. There's a lot of Pentax K FF lenses on the planet...

Ari

-- hide signature --

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Could be due to a technical limitation due to potential interference from the protruding aperture lever in K lenses. Nikon lenses have a similar lever and a nikon adapter is not listed on the webpage either.

An EF speedbooster with a EF-K adapter should work anyway, just temporarily remove the aperture lever if there is interference (the lever can be unscrewed on most pentax lenses).

Ayoh Regular Member • Posts: 210
Re: No speedbooster for Pentax lenses ;(...

Ayoh wrote:

Ari Aikomus wrote:

Ayoh wrote:

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

I wrote Metabones to enquire about a Pentax K to NEX adapter and this is the response:

Sorry! We have not planning to make a Pentax (speed booster)…..
Thank you!
Alex
GBI Ltd

Do not get them. There's a lot of Pentax K FF lenses on the planet...

Ari

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Could be due to a technical limitation due to potential interference from the protruding aperture lever in K lenses. Nikon lenses have a similar lever and a nikon adapter is not listed on the webpage either.

An EF speedbooster with a EF-K adapter should work anyway, just temporarily remove the aperture lever if there is interference (the lever can be unscrewed on most pentax lenses).

Actually having just looked at some photos of the adapter it looks like the lens elements are sufficiently well recessed to not interfere with the aperture lever. They already even have designed an adapter (a contarex mount) which has an aperture control ring which would be required for Pentax and Nikon lenses without aperture rings. They could just adapt that. Not sure why Pentax and Nikon are not available.

Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
Nikon speedbooster

Ayoh wrote:

Ayoh wrote:

Ari Aikomus wrote:

Ayoh wrote:

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

I wrote Metabones to enquire about a Pentax K to NEX adapter and this is the response:

Sorry! We have not planning to make a Pentax (speed booster)…..
Thank you!
Alex
GBI Ltd

Do not get them. There's a lot of Pentax K FF lenses on the planet...

Ari

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Could be due to a technical limitation due to potential interference from the protruding aperture lever in K lenses. Nikon lenses have a similar lever and a nikon adapter is not listed on the webpage either.

An EF speedbooster with a EF-K adapter should work anyway, just temporarily remove the aperture lever if there is interference (the lever can be unscrewed on most pentax lenses).

Actually having just looked at some photos of the adapter it looks like the lens elements are sufficiently well recessed to not interfere with the aperture lever. They already even have designed an adapter (a contarex mount) which has an aperture control ring which would be required for Pentax and Nikon lenses without aperture rings. They could just adapt that. Not sure why Pentax and Nikon are not available.

Nikon->NEX (and fuji) speedbooster will be coming.

http://www.dpreview.com/forums/post/51281348

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Ayoh Regular Member • Posts: 210
Re: Nikon speedbooster

Ari Aikomus wrote:

Ayoh wrote:

Ayoh wrote:

Ari Aikomus wrote:

Ayoh wrote:

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

I wrote Metabones to enquire about a Pentax K to NEX adapter and this is the response:

Sorry! We have not planning to make a Pentax (speed booster)…..
Thank you!
Alex
GBI Ltd

Do not get them. There's a lot of Pentax K FF lenses on the planet...

Ari

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Could be due to a technical limitation due to potential interference from the protruding aperture lever in K lenses. Nikon lenses have a similar lever and a nikon adapter is not listed on the webpage either.

An EF speedbooster with a EF-K adapter should work anyway, just temporarily remove the aperture lever if there is interference (the lever can be unscrewed on most pentax lenses).

Actually having just looked at some photos of the adapter it looks like the lens elements are sufficiently well recessed to not interfere with the aperture lever. They already even have designed an adapter (a contarex mount) which has an aperture control ring which would be required for Pentax and Nikon lenses without aperture rings. They could just adapt that. Not sure why Pentax and Nikon are not available.

Nikon->NEX (and fuji) speedbooster will be coming.

http://www.dpreview.com/forums/post/51281348

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

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.

Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
Re: Nikon speedbooster

Ayoh wrote:

Ari Aikomus wrote:

Nikon->NEX (and fuji) speedbooster will be coming.

http://www.dpreview.com/forums/post/51281348

-- hide signature --

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

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.

Indeed. This observation makes me think that it would be something more "behind lack of Pentax K lens support" - not technical reason!

Anyway - Could C/Y mount modified to accept Pentax K lenses? Kind of DIY work...Flange distance is same with Pentax K and C/Y.

Ari

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'Why should I feel lonely ? is not our planet in the Milky way?'

Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
Speedbooster works well.
1

BobORama wrote:

WHY would you want to use a product that reduces contrast and increases CA, when Instagram is free?

Actually it works surprisingly well:

http://www.eoshd.com/content/9485/metabones-speed-booster-adapter-full-review

at least 28-135mm range, it is designed for shorter than 200mm FF lenses.

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'Why should I feel lonely ? is not our planet in the Milky way?'

Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
Maybe Mitakon then...

It's very hard to understand why MetaBones is not interested Pentax K lens speedbooster...

But maybe Mitakon can understand better this maladministration, and to make such an adapter.

http://www.thephoblographer.com/2013/03/15/mitakon-to-do-pretty-much-what-metabones-did-with-the-speed-booster/

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viking79
viking79 Forum Pro • Posts: 14,137
Re: Metabones Speed Booster for Pentax K lenses?
1

BobORama wrote:

WHY would you want to use a product that reduces contrast and increases CA, when Instagram is free?

Because it allows you to use an APS-C camera effectively as a full frame camera.  It would be nice to be able to take that classic 50mm f/1.4 lens for Full Frame, and use it on APS-C and get effectively a 35mm f/0.93 lens as used on APS-C.

Sure, like a teleconverter, a telecompressor has issues.  You are using the entire full frame image circle now, and the telecompressor introduces some of its own aberrations, like extra distortion and some edge CA according to their graphs at metabones, but it also increases central resolution.

I suppose this question came up because it would allow using the FA 31, 43, and 77mm as full frame lenses as they were intended.

Eric

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Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
Re: Metabones Speed Booster for Pentax K lenses?

viking79 wrote:I suppose this question came up because it would allow using the FA 31, 43, and 77mm as full frame lenses as they were intended.

Indeed. And many other fine Pentax K lenses. I have seen a number of samples, and IQ have been pretty good.

So, I bought C/Y->NEX adapter. At least I can use my m42 Super Takumars as intended...And of course C/Y lenses, like Carl Zeiss gems.

But Pentax K speedbooster would be really necessary - would sell well too (even manual version). Once we do not even have the proper K-mount FF DSLR!

Ari

Eric

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BobORama
BobORama Senior Member • Posts: 2,195
Re: Speedbooster works well.

Ari Aikomus wrote:

BobORama wrote:

WHY would you want to use a product that reduces contrast and increases CA, when Instagram is free?

Actually it works surprisingly well:

http://www.eoshd.com/content/9485/metabones-speed-booster-adapter-full-review

at least 28-135mm range, it is designed for shorter than 200mm FF lenses.

When shooting video, with its astonishing 2MP stills, most of the optical gack introduced by the Metabones FR is concealed.   For video work, it may be passible.

The example stills from DRP's review show significant CA, some edge softness, some loss of contrast.   And of course any increase in real aperture will come with a decrease in contrast.   Look at the DPR stills.   Its pretty telling.

 BobORama's gear list:BobORama's gear list
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MightyMike Forum Pro • Posts: 35,699
Re: Speedbooster works well.
4

BobORama wrote:

Ari Aikomus wrote:

BobORama wrote:

WHY would you want to use a product that reduces contrast and increases CA, when Instagram is free?

Actually it works surprisingly well:

http://www.eoshd.com/content/9485/metabones-speed-booster-adapter-full-review

at least 28-135mm range, it is designed for shorter than 200mm FF lenses.

When shooting video, with its astonishing 2MP stills, most of the optical gack introduced by the Metabones FR is concealed.   For video work, it may be passible.

The example stills from DRP's review show significant CA, some edge softness, some loss of contrast.   And of course any increase in real aperture will come with a decrease in contrast.   Look at the DPR stills.   Its pretty telling.

You are mocking an adapter designed by one of the best optical designers in the world "Brian Caldwell", pretty much because you don't seem understand the concept and why adding glass can actually improve image quality. Brian Caldwell was the designer of this lens too...

https://www.lensrentals.com/rent/nikon/lenses/specialty/coastal-optics-uv-vis-ir-60mm-macro-for-nikon

Here is a very thorough review

http://www.lensrentals.com/blog/2013/01/metabones-magic

It clearly shows resolution increase with use of the adapter, in the center and average and the only drop is in the corners however such a drop is typical if you're using the whole image circle instead of the center portion.

As with any adapter (teleconverter or the speed booster) the overall quality depends on the combination of the parent lens and adapter, the best of both worlds might not give you the best overall result.

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Mike from Canada
"I am not a great photographer! God is a great creator! All I do is capture His creation with the tools He has provided me."
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KentG Veteran Member • Posts: 4,400
Re: Nikon speedbooster

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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ET2 Veteran Member • Posts: 4,076
Re: Nikon speedbooster

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.

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

Ari Aikomus
Ari Aikomus OP Veteran Member • Posts: 7,717
No, NO and no! yes, yes, YES!

ET2 wrote:

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.

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

You both are missing the point.

ET2...This Pentax-Nikon adapter use correction glass. Not a good thing - at all, especially with speedbooster!

KentG...metabones already planning Canon FD and Minolta MD lens support - both are dead systems! Pentax k system is still alive!

You said that "high overall quality" of Alpa, Contarex, C/Y, Leica R lenses would be some kind of reason why they offer speedbooster for these lenses over Pentax K... I say no

Pentax K is still alive mount, Pentax has some very HQ fullframe lenses and Pentax does not have its own FF DSLR - I would say that there were the three big YES why Metabones should produce speedbooster for Pentax K lenses.

Ari

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Tom Caldwell Forum Pro • Posts: 28,243
Re: Nikon speedbooster

Ayoh wrote:

Ari Aikomus wrote:

Ayoh wrote:

Ayoh wrote:

Ari Aikomus wrote:

Ayoh wrote:

Ari Aikomus wrote:

Hi,

Has anyone heard if the Metabones would be planned speedbooster adapter for Pentax K lenses? For example Pentax K--> NEX speedbooster ?

I was forced to purchase Metabones' speedbooster for Contax/Yashica (C/Y) --> NEX adapter , because it was the only way to get my M42 lenses to work with speedbooster. But you can't adapt Pentax K lenses that way.

There are already quite a few of the old lens mount supported, but not Pentax - which I think is a bit odd.

http://www.metabones.com/buy-speed-booster

I also know that Canon FD and Sony Alpha mount are coming later this year...

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Why not ask the designer, Brian Caldwell, himself:

http://www.dpreview.com/members/5764986886

If you find something out please report back.

I wrote Metabones to enquire about a Pentax K to NEX adapter and this is the response:

Sorry! We have not planning to make a Pentax (speed booster)…..
Thank you!
Alex
GBI Ltd

Do not get them. There's a lot of Pentax K FF lenses on the planet...

Ari

-- hide signature --

http://koti.mbnet.fi/tidis/AAikomus.jpg
- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

Could be due to a technical limitation due to potential interference from the protruding aperture lever in K lenses. Nikon lenses have a similar lever and a nikon adapter is not listed on the webpage either.

An EF speedbooster with a EF-K adapter should work anyway, just temporarily remove the aperture lever if there is interference (the lever can be unscrewed on most pentax lenses).

Actually having just looked at some photos of the adapter it looks like the lens elements are sufficiently well recessed to not interfere with the aperture lever. They already even have designed an adapter (a contarex mount) which has an aperture control ring which would be required for Pentax and Nikon lenses without aperture rings. They could just adapt that. Not sure why Pentax and Nikon are not available.

Nikon->NEX (and fuji) speedbooster will be coming.

http://www.dpreview.com/forums/post/51281348

-- hide signature --

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- Ari Aikomus -
'Why should I feel lonely ? is not our planet in the Milky way?'

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.

Dumb M42 to EF adapter works fine on the Speed Booster.

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Tom Caldwell

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