K-mount adapters for Pentax new-mount cameras

Started Sep 6, 2018 | Discussions
Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
More "camera body plus adapter" kits
1

There is a solidifying trend for on-line stores to offer "camera body + adapter" kits for the Nikon and Canon new-mount cameras.

(As well as camera bodies alone and "camera body + lens" kits).

The UK Nikon Store itself offers "Z-6 plus adapter" and "Z-7 plus adapter" kits.

Adorama also offers both of these kits.

I now think that these "camera body + adapter" kits are here to stay, and will be standard practice.

I don't think it is just a stop-gap because Nikon have started with only 3 Z-mount lenses, and Canon with only 4 R-mount lenses.

I think this is just a common sense view that lots of people will want these new-mount cameras to use with their SLR-mount lenses. Whether those users will add new-mount lenses later, or stick with SLR-mount lenses for the foreseeable future, will be personal (and unhurried) decisions.

I think the lesson for Pentax, if they are considering a new-mount mirrorless camera, is not to think that they must have new-mount lenses on day 1. (Perhaps 1 would be be useful for promotion, but I don't think it necessary).

Instead, they should emphasise from day 1 that their strategy is for existing K-mount lenses to continue to be "first class citizens" in their expanded eco-system. (A comprehensive adapter is important for making this story credible).

It would be necessary with every new lens being developed for Pentax to decide whether to make it with the existing K-mount or the new-mount.

I think the logic should be: "if there is little benefit either way, it should be K-mount, not new mount". That will have the biggest market without alienating Pentax users. And, of course, those lenses will work well on new-mount cameras via the adapter.

Over years, I would expect just a trickle of new-mount lenses, not a determined flood. (Hm! "Determined flood" from Pentax?) What constitutes sufficient benefit for a lens to be new-mount includes the extra quality likely from a better design for wide angle lenses. But it might also include lenses deliberately designed to be small and light.

I'm not sure what lessons can be drawn from the initial Nikon and Canon lenses:

Canon:

24-105mm f/4
28-70mm f/2
35mm f/1.8 macro
50mm f/1.2

Nikon:

24-70mm f/4
35mm f/1.8
50mm f/1.8

Mid-range zooms plus wide-aperture 35mm & 50mm. No long lenses.

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Skip py Contributing Member • Posts: 849
Re: K-mount adapters for Pentax new-mount cameras
1

Hi Barry

Thanks for sharing your thoughts with us and leading this interesting brainstorming about hypothetical Pentax products.

I guess that "squaring the circle" is the ultimate goal for Pentax / Ricoh :

1. keep mechanical AV/EV/AF for KAF lenses

2. in the mean time produce more lenses like PLM with good internal motors and WR

3. find a niche compatible with existing lenses and new PLM ones

If next Pentax can't focus my old lenses, then ... switch to Canon or Nikon or Sony. With such gems I'll manual focus as well (or even better) with other brands.

My two cents ...

Good, comfortable and weather sealed small bodies are the roots of Pentax, and they're probably working with this in mind today.

Good adapters are indeed the right move for MILC. Nikon and Canon just proved it : great achievement and another higher step for Pentax to improve its lineup.

1. Rear filters for KAF lenses should be nice, in body or in adapter. Lee Filters are great, but should be even greater inside the camera or at least inside a rear adapter : just keep in mind the rear filter in the lens design. The thickness of the filter(s) is part of the optical path and should lead to a small shift of the sensor plane if needed.

2. Tilt Shift adapter for Pentax's 645 lenses retaining AV/EV/AF capabilities would be a bless for landscape and architectural photographers: I guess that it's impossible with technologies available nowadays, at least at a reasonable cost?

In fact I'd love to use CPL or ND filters with my F* 250-600 lens if the dream comes true one day.

Thinking aloud, I'm not sure Pentax has to make smaller bodies to succeed. If a MILC with inbody filters can be the same size as current DSLR that's huge point : you only need to pick your tripod and continue shooting under the rain. Special UV, IR or full spectrum photography would be a nice side effect at a reasonable cost ... and more people would then try MightyMike's amazing experiments and find unsuspected beauties just around the corner!

Another side point : no new mount needed ! You just get EVF instead of OVF, with its pros and cons. Nice to have I think as a spare body for the K-1 ... or the other way round ?

Barry Pearson wrote:

I wonder if an adapter could incorporate a variable extension, equivalent to an extension tube? Perhaps this would introduce a new point of failure with a poor cost-benefit ratio.

Nice feature if it can be done without spoiling IQ and strenght of the system !

A switchable x1.4 TC would be nice to have too - like Canon's 200-400mm or Nikon's 180-400mm - but must be harder to design or incompatible with too many lenses ? I'd love to have one with the 150-450mm ... and switch it on occasions for that little more reach.

Best Regards, Fred

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Pentax K-3
Skip py Contributing Member • Posts: 849
Re: Another adapter variant . . . no motors + focus aid switch
1

TacticDesigns wrote:

. . . with mirrorless, would it be possible to just let the lens stop down as you turn the aperture dial on the lens.

(For lenses that don't have an aperture dial, a dial on the adapter would let you open up and close down the aperture.)

The camera then takes a light reading on the stopped down lens for exposure calculation. And then just brightens up the EVF or rear screen to make composing possible? Basically a WYSIWYG way of displaying the scene.

To help with manual focusing . . . there could be a lever on the right side of this adapter that you press with your middle finger on your right hand. Sort of like the opposite of a DOF preview button. So when you press this focus aid switch, it opens up the lens so that you can focus with the lens at the shallowest depth of field.

This switch could be locked into position so that you can just concentrate on focusing. And then be release for the actual picture.

But this switch could also be pushed and held to focus, and then just released to take the picture. Locking is an option, not a requirement.

I like the idea. I'll have to think more about it : seems interesting ...

Hey . . . maybe even bring in one for m42 auto lenses? So when you press the focus aid switch it would activate the auto aperture pin of the auto m42 lenses.

... even more if I can use my old K/M/m42 lenses !

Regards, Fred

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TacticDesigns
TacticDesigns Veteran Member • Posts: 6,179
Re: Another adapter variant . . . no motors + focus aid switch

Skip py wrote:

TacticDesigns wrote:

. . . with mirrorless, would it be possible to just let the lens stop down as you turn the aperture dial on the lens.

(For lenses that don't have an aperture dial, a dial on the adapter would let you open up and close down the aperture.)

The camera then takes a light reading on the stopped down lens for exposure calculation. And then just brightens up the EVF or rear screen to make composing possible? Basically a WYSIWYG way of displaying the scene.

To help with manual focusing . . . there could be a lever on the right side of this adapter that you press with your middle finger on your right hand. Sort of like the opposite of a DOF preview button. So when you press this focus aid switch, it opens up the lens so that you can focus with the lens at the shallowest depth of field.

This switch could be locked into position so that you can just concentrate on focusing. And then be release for the actual picture.

But this switch could also be pushed and held to focus, and then just released to take the picture. Locking is an option, not a requirement.

I like the idea. I'll have to think more about it : seems interesting ...

+1

Yeah. It's a bit of a weird idea.

I guess I see two downsides.

#1 Without an aperture actuator, the camera loses the ability to control the aperture on the lens, which means . . . no shutter priority mode, full program exposure mode, or for that matter, no fancy scene modes either. So the camera, with this adapter, would only be able to do metered manual and aperture priority.

I would be ok with that. It would be like going back to a Pentax K1000 or Pentax ME Super. I used both. My sister had a Pentax K1000 and I had a Pentax ME Super.

#2 With Pentax-M and m42 lenses . . . the aperture value is not automatically recorded to the EXIF data.

But it's not like we had this with Pentax-M and m42 lenses with any Pentax dSLR anyway, so its not like we are losing anything. A work around could be that you could use the front dial on the camera to dial in an aperture value that then gets recorded down to EXIF. So if you have the lens set to f/2 . . . you could just dial f/2 into the camera with the front dial and that would get recorded in the EXIF info.

I guess the way I look at it is . . . these are old lenses.

If I could get a nice metered manual and aperture priority mode on a modern full frame mirrorless camera, I'd be laughing!

If I want the full program mode, shutter priority or scene modes, I could either get the more expensive adapter (with built-in aperture actuator) or get native mirrorless lenses.

But . . . with the focus assist switch (reverse DOF preview button), it could add aperture priority to Pentax-M and m42 lenses, without the need to press the AE-L button to do a stopped down meter reading.

Hey . . . maybe even bring in one for m42 auto lenses? So when you press the focus aid switch it would activate the auto aperture pin of the auto m42 lenses.

... even more if I can use my old K/M/m42 lenses !

+1

LOL.

I sold off my Pentax 50mm f/1.4 m42 mount lens. I'm kicking myself for doing so. LOL.

A built-in switch to stop down / open up the lens would make it easier to use a m42 lens. And if there is an adapter, there would probably be space to put in a switch to push / release that m42 pin on the lens mount.

For me . . . a big bonus potential of mirrorless is to bring back the match needle metering in the viewfinder.

The last film camera I used was my sister's Pentax K1000. And I still remember how fun and simple it was to use that match needle metering system.

I can understand why this system isn't used in dSLR cameras. LOL.

But for mirrorless cameras with an electronic viewfinder . . . it would just be a program running to display the current meter reading as a needle in the viewfinder.

That . . . would be cool!

Take care & Happy Shooting!

Regards, Fred

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Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
Re: K-mount adapters for Pentax new-mount cameras

Skip py wrote:

Hi Barry

Thanks for sharing your thoughts with us and leading this interesting brainstorming about hypothetical Pentax products.

I guess that "squaring the circle" is the ultimate goal for Pentax / Ricoh :

1. keep mechanical AV/EV/AF for KAF lenses

2. in the mean time produce more lenses like PLM with good internal motors and WR

I assume that is the future for premium Pentax lenses. (Will they all be KA4?)

The new D FA* 50mm f/1.4 has no mechanical coupling. Quiet. Fast. All weather.

3. find a niche compatible with existing lenses and new PLM ones

If next Pentax can't focus my old lenses, then ... switch to Canon or Nikon or Sony. With such gems I'll manual focus as well (or even better) with other brands.

My two cents ...

Good, comfortable and weather sealed small bodies are the roots of Pentax, and they're probably working with this in mind today.

"Small" isn't my highest priority. (But see the photos at the end). And the size and weight of lenses needs to be taken into account. It is tricky to make a a light long FF lens.

But Nikon are using a Fresnel technique to make a significant improvement, so I am optimistic about the possibilities.

Good adapters are indeed the right move for MILC. Nikon and Canon just proved it : great achievement and another higher step for Pentax to improve its lineup.

It is interesting to note the number of "camera back plus adapter" kits/bundles already being offered by major retailers for those new Nikon and Canon cameras.

Not only would a comprehensive adapter be essential for Pentax, but I'm sure such a kit/bundle would be popular for people wanting to exploit all their existing K-mount lenses. Or to be able to buy new K-mount lenses to use on such a Pentax new-mount mirrorless camera.

A good adapter enables both the manufacturer and the purchaser to develop their systems incrementally.

1. Rear filters for KAF lenses should be nice, in body or in adapter. Lee Filters are great, but should be even greater inside the camera or at least inside a rear adapter : just keep in mind the rear filter in the lens design. The thickness of the filter(s) is part of the optical path and should lead to a small shift of the sensor plane if needed.

The Canon "Drop-In Filter Mount Adapter EF-EOS R", which is currently offered with a "Variable neutral density filter" and a "Circular polarising filter", comes complete with a drop-in plain glass non-filter to use when not using the filters. I would expect it to avoid such a shift.

2. Tilt Shift adapter for Pentax's 645 lenses retaining AV/EV/AF capabilities would be a bless for landscape and architectural photographers: I guess that it's impossible with technologies available nowadays, at least at a reasonable cost?

I have no idea! I use the Samyang T-S 24mm F3.5 ED AS UMC .

In fact I'd love to use CPL or ND filters with my F* 250-600 lens if the dream comes true one day.

Thinking aloud, I'm not sure Pentax has to make smaller bodies to succeed. If a MILC with inbody filters can be the same size as current DSLR that's huge point : you only need to pick your tripod and continue shooting under the rain. Special UV, IR or full spectrum photography would be a nice side effect at a reasonable cost ... and more people would then try MightyMike's amazing experiments and find unsuspected beauties just around the corner!

Another side point : no new mount needed ! You just get EVF instead of OVF, with its pros and cons. Nice to have I think as a spare body for the K-1 ... or the other way round ?

Yes. We can think of using such a new-mount body to complement our existing SLRs. We shouldn't automatically assume they will replace them.

Barry Pearson wrote:

I wonder if an adapter could incorporate a variable extension, equivalent to an extension tube? Perhaps this would introduce a new point of failure with a poor cost-benefit ratio.

Nice feature if it can be done without spoiling IQ and strenght of the system !

A switchable x1.4 TC would be nice to have too - like Canon's 200-400mm or Nikon's 180-400mm - but must be harder to design or incompatible with too many lenses ? I'd love to have one with the 150-450mm ... and switch it on occasions for that little more reach.

I was on a workshop with someone using that Canon lens. It is far too heavy for me! Nearly 4 kilograms, and a price that appears to be based on its weight in gold!

I'm currently experimenting with the Pentax DA 1.4x converter on the D FA 150-450mm lens.

A few comparisons among my own camera bodies for amusement:

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Anders_Nilsson Contributing Member • Posts: 559
Re: K-mount adapters for Pentax new-mount cameras

I also urge Ricoh to give away the mount for free. Then all crafty Chinese could develop smart adapters for all lovely old MF gear.

I would like an adapter for Minolta MF that has a built in focuser that gives AF when coupled with the OSPDAF. And it should have a camera that reads the focal length indication on the lens barrel and sends correct EXIF to the camera  The adapter focuser can take care of telling the camera the focusing distance, especially when paired with a laser AF module from a smartphone.

This could give the Rico MF system a sales boost, Rico has to specialize and try to penetrate the niche markets.

Ricoh should set the mount standard and develop the bodies but let the Chinese develop smart accessories. Also with an open mount standard third party could develop and sell lens correction profiles since the camera serial number is accessible. Sony had similar ideas but never carried through  I really think the Chinese aftermarket industry can be helpful. Lego Mindstorm had a similar approach and it saved Lego. Also astrophotography should continue with Ricoh.

Please call me crazy if you wish.... At least I have dreams.

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Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
The size and weight of an adapter

In order to get a feel for the size and weight of the Nikon FTZ Mount Adapter, I've compared it with something I know, the Pentax DA 1.4x Rear Converter.

Nikon FTZ Mount Adapter

Diameter: 70mm (?)
Height: 80mm
Casing size, front to back: about 30mm
Weight: 135 grams

Pentax DA 1.4x Rear Converter

Diameter: 65mm
Casing size, front to back: 20mm
Weight: 126 grams

(I'm not making a particular point here!)

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Mark Ransom
Mark Ransom Veteran Member • Posts: 5,735
Re: K-mount adapters for Pentax new-mount cameras

Even if the depth is enough for focus and aperture motors, what about the width? The adapter is going to be very ungainly. I could see a protrusion on the bottom but I wonder if it would be enough, because you wouldn't want it going past the bottom of the camera.

Edit: somebody pointed out Sony's LA-EA4 adapter which does exactly what I describe, so obviously it's possible. Definitely ungainly though, and expensive for what it is.

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Alex Sarbu Forum Pro • Posts: 10,139
Re: K-mount adapters for Pentax new-mount cameras

Mark Ransom wrote:

Even if the depth is enough for focus and aperture motors, what about the width? The adapter is going to be very ungainly. I could see a protrusion on the bottom but I wonder if it would be enough, because you wouldn't want it going past the bottom of the camera.

It shouldn't be larger than the Sony LA-EA4, which includes a PDAF system in addition to mechanical aperture control and screw drive AF.

Besides, people who insist on using mirrorless should suffer!

Alex

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Mark Ransom
Mark Ransom Veteran Member • Posts: 5,735
Re: "Camera body plus adapter" bundles

A smart retailer would offer similar bundles with Sony cameras and adapters for Canon or Nikon lenses.

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TacticDesigns
TacticDesigns Veteran Member • Posts: 6,179
Another far out there idea . . .

TacticDesigns wrote:

Skip py wrote:

TacticDesigns wrote:

. . . with mirrorless, would it be possible to just let the lens stop down as you turn the aperture dial on the lens.

(For lenses that don't have an aperture dial, a dial on the adapter would let you open up and close down the aperture.)

The camera then takes a light reading on the stopped down lens for exposure calculation. And then just brightens up the EVF or rear screen to make composing possible? Basically a WYSIWYG way of displaying the scene.

To help with manual focusing . . . there could be a lever on the right side of this adapter that you press with your middle finger on your right hand. Sort of like the opposite of a DOF preview button. So when you press this focus aid switch, it opens up the lens so that you can focus with the lens at the shallowest depth of field.

This switch could be locked into position so that you can just concentrate on focusing. And then be release for the actual picture.

But this switch could also be pushed and held to focus, and then just released to take the picture. Locking is an option, not a requirement.

I like the idea. I'll have to think more about it : seems interesting ...

+1

Yeah. It's a bit of a weird idea.

I guess I see two downsides.

#1 Without an aperture actuator, the camera loses the ability to control the aperture on the lens, which means . . . no shutter priority mode, full program exposure mode, or for that matter, no fancy scene modes either. So the camera, with this adapter, would only be able to do metered manual and aperture priority.

I would be ok with that. It would be like going back to a Pentax K1000 or Pentax ME Super. I used both. My sister had a Pentax K1000 and I had a Pentax ME Super.

#2 With Pentax-M and m42 lenses . . . the aperture value is not automatically recorded to the EXIF data.

But it's not like we had this with Pentax-M and m42 lenses with any Pentax dSLR anyway, so its not like we are losing anything. A work around could be that you could use the front dial on the camera to dial in an aperture value that then gets recorded down to EXIF. So if you have the lens set to f/2 . . . you could just dial f/2 into the camera with the front dial and that would get recorded in the EXIF info.

I guess the way I look at it is . . . these are old lenses.

If I could get a nice metered manual and aperture priority mode on a modern full frame mirrorless camera, I'd be laughing!

If I want the full program mode, shutter priority or scene modes, I could either get the more expensive adapter (with built-in aperture actuator) or get native mirrorless lenses.

But . . . with the focus assist switch (reverse DOF preview button), it could add aperture priority to Pentax-M and m42 lenses, without the need to press the AE-L button to do a stopped down meter reading.

Hey . . . maybe even bring in one for m42 auto lenses? So when you press the focus aid switch it would activate the auto aperture pin of the auto m42 lenses.

... even more if I can use my old K/M/m42 lenses !

+1

LOL.

I sold off my Pentax 50mm f/1.4 m42 mount lens. I'm kicking myself for doing so. LOL.

A built-in switch to stop down / open up the lens would make it easier to use a m42 lens. And if there is an adapter, there would probably be space to put in a switch to push / release that m42 pin on the lens mount.

For me . . . a big bonus potential of mirrorless is to bring back the match needle metering in the viewfinder.

The last film camera I used was my sister's Pentax K1000. And I still remember how fun and simple it was to use that match needle metering system.

I can understand why this system isn't used in dSLR cameras. LOL.

But for mirrorless cameras with an electronic viewfinder . . . it would just be a program running to display the current meter reading as a needle in the viewfinder.

That . . . would be cool!

Take care & Happy Shooting!

Regards, Fred

Ok.

Here's another far out there idea . . . LOL.

The above adapter for m42, Pentax-M and Pentax-A lenses . . . but with . . .

a built-in pellicle mirror, OVF and . . . split image focus screen!!!

So . . . still no electronics.

Only moving part is the focus aid switch (reverse DOF preview button), but turning a mirrorless camera into a Pentax K1000 or Pentax ME Super!

I totally have no idea if there is space enough in an adapter for something like that.

But that would be pretty cool!

LOL.

Take care & Happy Shooting!

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DougOB
DougOB Senior Member • Posts: 1,107
Re: The size and weight of an adapter

Barry Pearson wrote:

In order to get a feel for the size and weight of the Nikon FTZ Mount Adapter, I've compared it with something I know, the Pentax DA 1.4x Rear Converter.

Nikon FTZ Mount Adapter

Diameter: 70mm (?)
Height: 80mm
Casing size, front to back: about 30mm
Weight: 135 grams

Pentax DA 1.4x Rear Converter

Diameter: 65mm
Casing size, front to back: 20mm
Weight: 126 grams

(I'm not making a particular point here!)

A naive, and possibly stupid,  question... does a mount adapter need to have any glass in it?  Or simply Mount A to mount B, a bit of a spacer, and circuit/control pass though?

Having said that I believe that my K-to-Q converter is much more complicated than that...

Doug

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Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
Re: K-mount adapters for Pentax new-mount cameras

Mark Ransom wrote:

Even if the depth is enough for focus and aperture motors, what about the width? The adapter is going to be very ungainly. I could see a protrusion on the bottom but I wonder if it would be enough, because you wouldn't want it going past the bottom of the camera.

Edit: somebody pointed out Sony's LA-EA4 adapter which does exactly what I describe, so obviously it's possible. Definitely ungainly though, and expensive for what it is.

This suggests that it 159 grams:
https://www.amazon.co.uk/Sony-LAEA4-Frame-Mount-Adapter/dp/B00G9UJYCK

The Pentax DA 1.4x Rear Converter is 126 grams. I barely notice that I'm carrying that.

My K-1ii weighs 1010 grams without battery grip or lens. What would a Pentax new-mount mirrorless camera weigh?

(A Nikon Z 7 body weighs 675 grams. 335 grams lighter than my K-1ii).

I don't think it is expensive for what it does. It would be a one-off purchase. And I suspect that it would cheaper as part of a bundle/kit with a camera back. That appears to be what is happening with the new Nikons and Canons.

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TacticDesigns
TacticDesigns Veteran Member • Posts: 6,179
Re: The size and weight of an adapter

DougOB wrote:

Barry Pearson wrote:

In order to get a feel for the size and weight of the Nikon FTZ Mount Adapter, I've compared it with something I know, the Pentax DA 1.4x Rear Converter.

Nikon FTZ Mount Adapter

Diameter: 70mm (?)
Height: 80mm
Casing size, front to back: about 30mm
Weight: 135 grams

Pentax DA 1.4x Rear Converter

Diameter: 65mm
Casing size, front to back: 20mm
Weight: 126 grams

(I'm not making a particular point here!)

A naive, and possibly stupid, question... does a mount adapter need to have any glass in it? Or simply Mount A to mount B, a bit of a spacer, and circuit/control pass though?

An adapter needs corrective lenses in it if the flange focal distance between lens and sensor becomes greater than what the lens was originally designed for, if you want to be able to focus to infinity.

That is why I would need glass in an adapter if I wanted to use my old Pentax SLR lenses on my Nikon dSLR camera and be able to focus to infinity.

But with mirrorless cameras, there is a much smaller flange focal distance . . . so it is possible (most of the time?) to design an adapter to use SLR lenses on a mirrorless body without needing corrective lenses.

Having said that I believe that my K-to-Q converter is much more complicated than that...

Yes.

The Pentax K-to-Q adapter has a built-in shutter, since the camera itself does not have a shutter.

Take care & Happy Shooting!

Doug

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Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
Re: The size and weight of an adapter

DougOB wrote:

Barry Pearson wrote:

In order to get a feel for the size and weight of the Nikon FTZ Mount Adapter, I've compared it with something I know, the Pentax DA 1.4x Rear Converter.

Nikon FTZ Mount Adapter

Diameter: 70mm (?)
Height: 80mm
Casing size, front to back: about 30mm
Weight: 135 grams

Pentax DA 1.4x Rear Converter

Diameter: 65mm
Casing size, front to back: 20mm
Weight: 126 grams

(I'm not making a particular point here!)

A naive, and possibly stupid, question... does a mount adapter need to have any glass in it? Or simply Mount A to mount B, a bit of a spacer, and circuit/control pass though?

Unless I'm missing something specific to Pentax K-mount, it would have no glass.

Having said that I believe that my K-to-Q converter is much more complicated than that...

Yes, so is mine! But it doesn't have glass in it either.

It is complicated partly because of aperture control and shutter:
http://www.gyes.eu/documents/pentaxqkadapter.pdf

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Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
My new-mount mirrorless walk-around system
1

I often use my K-1ii plus D FA 28-105mm lens as a "walk-around system".

And I've used this combination for all the "air to air" and "air to ground" photos I've taken in the last few years. (Often using Live View rather than mirror-mode):

Air to ground photos from a helicopter

Air-to-air photos (and air-to-ground)

Here is a comparison of that combination with a (hypothetical) Pentax FF new-mount mirrorless camera plus (hypothetical) Pentax new-mount FF mid-range zoom.

...

Weight of K-1ii: 1010 grams.

Weight of D FA 28-105mm: 440 grams

Combination: 1450 grams.

...

Weight of Nikon Z 7: 675 grams.

Given the Pentax skills in relatively light cameras, I'll assume that a Pentax new-mount FF mirrorless camera would be 600 grams.

I'll assume that a Pentax new-mount moderate-aperture FF mid-range zoom lens could be 400 grams. [Ref 1] [Ref 2]

Combination of Pentax FF new-mount mirrorless camera + new-mount mid-range FF zoom: 1000 grams.

1000 grams instead of 1450 grams! And probably smaller.

If such a camera and such a lens were released by Pentax, I would buy them as soon as I could afford them! [Ref 3] [Ref 4]

...

[1] Would there be such a new-mount mid-range zoom? Both Canon and Nikon have announced mid-range zooms with their new cameras. If Pentax only released 1 new-mount lens with their (hypothetical) new-mount mirrorless FF camera, it would probably be a mid-range zoom. And probably not one with an especially large aperture.

[2] Would a Pentax short-registration mid-range zoom be lighter than the D FA 28-105mm? I'm guessing here. It could certainly omit the aperture lever.

[3] I'm judging this combination from the view of a simple "walk-around system". Not from whether it could support hours of shooting motorsports or "aircraft in flight". I would expect those to use my existing FF K-mount equipment, at least for many years.

[4] I would expect bundles/kits of "camera back plus adapter", "camera back plus mid-range zoom", and perhaps "camera back plus mid-range zoom plus adapter". That appears to be happening with the new Canon and Nikon cameras.

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Ricoh WG-6 Panasonic LX100 Ricoh GR III Pentax K-7 Pentax K-3 II +27 more
Skip py Contributing Member • Posts: 849
Re: K-mount adapters for Pentax new-mount cameras
1

Barry Pearson wrote:

The new D FA* 50mm f/1.4 has no mechanical coupling. Quiet. Fast. All weather.

Still having an eye on this one but I already have the old F f/1.7, so ...

3. find a niche compatible with existing lenses and new PLM ones

If next Pentax can't focus my old lenses, then ... switch to Canon or Nikon or Sony. With such gems I'll manual focus as well (or even better) with other brands.

My two cents ...

Good, comfortable and weather sealed small bodies are the roots of Pentax, and they're probably working with this in mind today.

"Small" isn't my highest priority. (But see the photos at the end). And the size and weight of lenses needs to be taken into account. It is tricky to make a a light long FF lens.

But Nikon are using a Fresnel technique to make a significant improvement, so I am optimistic about the possibilities.

I still have the Canon 400mm f/5.6 just in case, but this one is really disturbing, especially with Z6 (or Z7) with an adapter making good use of such a lens ! If this adapter had a rear filter like Canon's one - and if I had the ca$h ! - I'd probably go with Nikon.

Not only would a comprehensive adapter be essential for Pentax, but I'm sure such a kit/bundle would be popular for people wanting to exploit all their existing K-mount lenses. Or to be able to buy new K-mount lenses to use on such a Pentax new-mount mirrorless camera.

Dreaming of using other mount lenses is a big plus with short registration, if Pentax or third party offer such an option. It reminds me of a small company providing a M mount camera (sort of)

https://www.youtube.com/watch?v=E1FCwJMdWVM

The Canon "Drop-In Filter Mount Adapter EF-EOS R", which is currently offered with a "Variable neutral density filter" and a "Circular polarising filter", comes complete with a drop-in plain glass non-filter to use when not using the filters. I would expect it to avoid such a shift.

This Canon with Variable ND and CPL is really a great move. I'd like to know what are the caracteristics of drop-in replacement : thickness and index for equivalent optical path. It's common for lenses but I was refering to the shift needed for inbody filters : the body would have to be a little thicker. If IQ is good enough, using slimmer filters would be good for price, weight and body dimensions!

2. Tilt Shift adapter for Pentax's 645 lenses retaining AV/EV/AF capabilities would be a bless for landscape and architectural photographers: I guess that it's impossible with technologies available nowadays, at least at a reasonable cost?

I have no idea! I use the Samyang T-S 24mm F3.5 ED AS UMC .

I'm still using the old Pentax 28mm Shift lens but I'd be curious to see how Pentax/Ricoh could bring a competitor to ARAX TS adaptor for AF 645 lenses keeping autofocus and metering. Too specialised ? But what a challenge for engineers !

A switchable x1.4 TC would be nice to have too - like Canon's 200-400mm or Nikon's 180-400mm - but must be harder to design or incompatible with too many lenses ? I'd love to have one with the 150-450mm ... and switch it on occasions for that little more reach.

I was on a workshop with someone using that Canon lens. It is far too heavy for me! Nearly 4 kilograms, and a price that appears to be based on its weight in gold!

I'm currently experimenting with the Pentax DA 1.4x converter on the D FA 150-450mm lens.

That was exactly my point : a x1.4 TC you could leave (or not) on the body for occasional longer reach (switch on or off on the road). I like the crop mode with this lens for easier framing, but closer look is sometime a must.

Penalty of only 350g for a combo (rear filter + x1.4) seems fair ?

I'm optimistic on this one (121g for Canon's adapter with rear filter + 225g for the x1.4).

I'd gladly add it to my "walk-around system" : I mean the K-1'' + D FA 150-450mm

A few comparisons among my own camera bodies for amusement:

I like your comparison with Z1P and K-1 !

Some room for improvements...

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Pentax K-3
Barry Pearson
OP Barry Pearson Veteran Member • Posts: 8,723
Summary of "adapters" @ 2018-09-08
2

For various reasons I wanted to explore what Nikon and Canon are up to with their new-mount mirrorless cameras. I especially wanted to form a view about the potential lessons for the future of Pentax equipment.

Key items are their lens-mount adapters, and I started this thread to identify the implications of these, and record what I found. In the last few days, I've discovered a lot, from what others have posted in this thread and elsewhere, and by examining external sources.

This page is an attempt to summarise what I've learned at 8th September, and to add analysis and guesses and my own opinions. (I may post updated summaries in future).

New mounts are a good idea for new ranges of mirrorless cameras

I started a thread about various options that Pentax might adopt:

Some mirrorless options for Pentax

I was slightly in favor of not developing a new short registration mount. Posts from other people, and further analysis, show I was wrong. If Pentax mirrorless APS-C and/or FF cameras are introduced, they should use such a new mount.

Pentax should also release a good lens-mount adapter from the start.

Adapters can be fully featured

Examples posted by others, and further searches by me, show that a Pentax lens mount adapter could support features of older Pentax lenses, such the aperture lever and screw-focusing.

I believe it should do so. (Or if Pentax releases more than one adapter, at least of them should do so). This is for a variety of reasons:

Avoiding alienation of K-mount users with an investment in K-mount lenses.
Avoiding the need for an aggressive/impossible lens-delivery schedule.

Canon and Nikon new-mount lens schedule

The Nikon new-mount lens roadmap for 2018/2019/2020 is instructive. The longest lens is a 70-200mm zoom. The second longest lens is an 85mm prime. [Ref 2]

I haven't found a Canon RF-mount roadmap. But Canon and Nikon are starting with mid-range zooms, and 35mm and 50mm primes. No long lenses. [Ref 1]

Canon's and Nikon's own UK Stores give the following numbers of FF lenses:

Nikon: 77 (plus 3 Teleconverters)

Canon: 54 (not including M-mount) + 13 APS-C lenses and 2 Teleconverters.

These include: normal and telephoto zooms, primes, macro lens, tilt-shift lenses, and manual focus lenses. (Plus those Teleconverters).

Neither Canon nor Nikon could cover that range with new-mount lenses for many years, if ever.

Adapters will be strategic items in the Canon and Nikon catalogues

This follows from the above. But it is also essential from the user-perspective.

Many users of the new cameras will start with just the camera plus an adapter.

Many users of the new cameras will continue to use at least some SLR-mount lenses with those cameras for very many years, perhaps the rest of their lives!

These adapters must not be treated only as temporary/tactical items. They are here to stay, possibly with the occasional upgrade.

Weights and sizes (and prices) of adapters

For illustration:

The Nikon Z 7 weighs 335 grams less than a K-1-series. The Nikon "Mount Adapter FTZ" weighs 135 grams. Even with an adapter fitted, the Z 7 weighs less than a K-1-series.

These adapters weigh vastly less than many of the current Canon and Nikon lenses they will be used with.

Analogy with Teleconverters

Teleconverters are different types of equipment! But they share a feature of lens-mount adapters: their users fit them between their camera bodies and their lenses.

Teleconverters typically cost a lot more than these lens-mount adapters. And they typically weigh more. (The Pentax DA 1.4x Rear Converter is an exception at 126 grams).

For example, Canon Teleconverters may weigh 200+ or 300+ grams. Nikon's, from nearly 200 to about 300 grams. Tamron's and Kenko's, either side of 200 grams.

People don't appear to complain about the weights of their Teleconverters, even though they are typically heavier than the new-mount adapters. I don't believe the weights (or prices) of these adapters will be much of an issue with users.

Prices of adapters

I'm not seeing what I would consider to be excessive prices for the adapters.

(Although I suspect the Canon "Drop-In Filter Mount Adapter" plus the drop-in filters themselves will be too expensive for many people).

I also also observe kits/bundles, which considerably reduce their price. "Camera back plus adapter", or "Camera back plus mid-range zoom plus adapter".

Lessons for Pentax

The first lesson for Ricoh management is that these new systems from Canon and Nikon are changing the marketplace compared with a year ago, and any decisions based on last year's situation need to be re-visited.

(Perhaps this will confirm whatever decision they made last year. Or perhaps not).

If they haven't already started development, (and I have no evidence that they have), it will take X years before they can release their first such camera. What will be important isn't what the environment and market is now, but what it will be in X years time.

And that will be significantly different from now, as evidence and experience appear, more Canon and Nikon new-mount cameras appear, and some existing Pentax users adapt to the new situation.

I've already thought about what my reaction might be to a mirrorless FF camera: probably positive . (Perhaps not so positive about an APS-C camera).

References

[1] Initial lenses:

Nikon:
24-70mm f/4
35mm f/1.8
50mm f/1.8

Canon:
24-105mm f/4
28-70mm f/2
35mm f/1.8 macro
50mm f/1.2

[2] Nikon 3-year roadmap:

Nikon roadmap for their new-mount lenses.

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Ricoh WG-6 Panasonic LX100 Ricoh GR III Pentax K-7 Pentax K-3 II +27 more
DougOB
DougOB Senior Member • Posts: 1,107
Re: Summary of "adapters" @ 2018-09-08

Barry Pearson wrote:

For various reasons I wanted to explore what Nikon and Canon are up to with their new-mount mirrorless cameras. I especially wanted to form a view about the potential lessons for the future of Pentax equipment.

Key items are their lens-mount adapters, and I started this thread to identify the implications of these, and record what I found. In the last few days, I've discovered a lot, from what others have posted in this thread and elsewhere, and by examining external sources.

This page is an attempt to summarise what I've learned at 8th September, and to add analysis and guesses and my own opinions. (I may post updated summaries in future).

New mounts are a good idea for new ranges of mirrorless cameras

I started a thread about various options that Pentax might adopt:

Some mirrorless options for Pentax

I was slightly in favor of not developing a new short registration mount. Posts from other people, and further analysis, show I was wrong. If Pentax mirrorless APS-C and/or FF cameras are introduced, they should use such a new mount.

Pentax should also release a good lens-mount adapter from the start.

It still depends on what a new mount is.  Is it essentially a KAF4 mount with a shorter flange, or is it something so different that proper adapters need to be very complicated.

I would say that the Q followed the latter approach, but maybe lessons can be learned.

Doug

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Mark Ransom
Mark Ransom Veteran Member • Posts: 5,735
Re: Summary of "adapters" @ 2018-09-08
1

DougOB wrote:

Barry Pearson wrote:

For various reasons I wanted to explore what Nikon and Canon are up to with their new-mount mirrorless cameras. I especially wanted to form a view about the potential lessons for the future of Pentax equipment.

Key items are their lens-mount adapters, and I started this thread to identify the implications of these, and record what I found. In the last few days, I've discovered a lot, from what others have posted in this thread and elsewhere, and by examining external sources.

This page is an attempt to summarise what I've learned at 8th September, and to add analysis and guesses and my own opinions. (I may post updated summaries in future).

New mounts are a good idea for new ranges of mirrorless cameras

I started a thread about various options that Pentax might adopt:

Some mirrorless options for Pentax

I was slightly in favor of not developing a new short registration mount. Posts from other people, and further analysis, show I was wrong. If Pentax mirrorless APS-C and/or FF cameras are introduced, they should use such a new mount.

Pentax should also release a good lens-mount adapter from the start.

It still depends on what a new mount is. Is it essentially a KAF4 mount with a shorter flange, or is it something so different that proper adapters need to be very complicated.

I would say that the Q followed the latter approach, but maybe lessons can be learned.

There's no point in creating a new mount if it carries the baggage from the old mount. There's no way a new mount would have an AF motor or aperture lever, since modern lenses don't need them and they would be an unnecessary expense in the camera.

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Pentax K-7 Pentax K-01 Olympus E-M5 II Pentax smc DA 15mm F4 ED AL Limited Pentax smc DA 18-135mm F3.5-5.6ED AL [IF] DC WR +6 more
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