The new Nikon mirrorless system

[Birna Rørslett]

Changing distance of the lens-to-film plane will make a lens focus farther or closer, or not be able to focus at all. One might be able to get a particular lens to focus closer than usual or going to infinity, but once the lens is outside the design parameters, image quality will suffer, some times dramatically so. The so-called 'X-ray' lenses (Rodenstock etc.) are prime examples of this optical fact. Even adding extension with no glass inside can influence performance badly.

An interesting lens for the Z might be the Nikkor-O 55/1.2. As it will focus to infinity on say a 1 Nikon CX or m43 camera, it should be able to do the same on an Z. However, image quality declines sharply on these small-format cameras, and combined with a Z body, in all likelihood deteriorates further. Might be interesting nevertheless. I certainly will experiment with the combination once my Z cameras arrive.

A final point is noticing one will not get a wider view on the Z, just wider range of focusing, with a lens such as the 55/1.2

[Seapy]

Michael, in principle making these mounts is simple, a block of aluminium, a lathe, a Dremel and a couple of files.

Making the Z mount bayonet isn't difficult, no more so than the F mount, it's a straightforward turning operation.  Having done that, all you have to do is machine the lens mount of choice, which is likely not hard either, bayonet or screw.  Someone with a modern CNC lathe could knock them out for fun. As fast as they can cut the blanks off a length of aluminium.

One trick idea would be to create a helicoid within the Z mount adaptor, again not difficult, single, double even quad start threads are entirely possible with ease on CNC machines.  That would enable whatever focus throw you desired.

Make friends with your local CNC machine shop or a keen model engineer.  Mechanically, anything is possible with the Z mount.

[Erik Lund]

Michael, in principle making these mounts is simple, a block of aluminium, a lathe, a Dremel and a couple of files.

Making the Z mount bayonet isn't difficult, no more so than the F mount, it's a straightforward turning operation.  Having done that, all you have to do is machine the lens mount of choice, which is likely not hard either, bayonet or screw.  Someone with a modern CNC lathe could knock them out for fun. As fast as they can cut the blanks off a length of aluminium.

One trick idea would be to create a helicoid within the Z mount adaptor, again not difficult, single, double even quad start threads are entirely possible with ease on CNC machines.  That would enable whatever focus throw you desired.

Make friends with your local CNC machine shop or a keen model engineer.  Mechanically, anything is possible with the Z mount.

Sorry but this must have been written with a lot of    and/or 
Such a mount as the F or Z- will be extremely expensive to make in a series of 1!
To start off it's not just ordinary aluminium, ofcourse you could get away with it but,,, the tolerances etc. not something you just do, the geometry of these mounts are in fact very complex!
You make it sound like making a focusing mechanism that don't rotate is piece of cake, sorry I don't get it,,,?


Sure you can get cheap copies but that is a whole other story!

[Erik Lund]

Here is a drawing of the F-mount

[Thomas Stellwag]

OT  Erik, I´d like this drawing for a print on a T - is it protected?

[Michael Erlewine]

So, I used the wrong term "wide view," when what I meant was range of focus. I use the Nikkor "O" CRT lens a lot, as well as many other "exotic" lenses, but the focus range often is very restricted. I would like to know what to ask for if I want the Nikkor "O" lens to have a larger focus range? Obviously, an adapter with a built-in helicoid that ranged from less than an F-Mount to the standard F-Mount would be perfect. However, would not adapters like 39-mm and M42 also do this? And I know that any change will mess with the optics to some degree, but with the Nikkor "O" (which already is gifted with strange optics) might not be worse for more focus range. I am just learning here.

[Erik Lund]

OT  Erik, I´d like this drawing for a print on a T - is it protected?

The images are available on Wiki:
https://en.wikipedia.org/wiki/Nikon_F-mount
It's a png file I have no idea about the copyrights

[Erik Lund]

So, I used the wrong term "wide view," when what I meant was range of focus. I use the Nikkor "O" CRT lens a lot, as well as many other "exotic" lenses, but the focus range often is very restricted.


1. I would like to know what to ask for if I want the Nikkor "O" lens to have a larger focus range?


2. Obviously, an adapter with a built-in helicoid that ranged from less than an F-Mount to the standard F-Mount would be perfect.


3. However, would not adapters like 39-mm and M42 also do this?


And I know that any change will mess with the optics to some degree, but with the Nikkor "O" (which already is gifted with strange optics) might not be worse for more focus range. I am just learning here.

1. An adapter with build in focus: Female Leica M39 thread mount (39mm) - to - Nikon camera Z-mount


2. A. Yes it can be more or less the length of an FTZ adapter, just with focus, depends on what is needed.


2. B. Yes Voigtlander makes such an adapter for Leica M on Sony A7, so just have patience and someone might make one and offer them online at some point in time, here a nice gentleman show it to you:


https://www.youtube.com/watch?v=fc5FqNIB5rc


3. Adapters usually don't have focusing build in, if your thinking using the new Nikon FTZ with an adapter, it will do absolutely no difference to your current Nikon D850 setup in any way or form regarding range or view.

[richardHaw]

brass should be better but heavy

oh, it's Tom! (RIP)

our best bet is amedeo muscelli

[Michael Erlewine]

1. An adapter with build in focus: Female Leica M39 thread mount (39mm) - to - Nikon camera Z-mount


2. A. Yes it can be more or less the length of an FTZ adapter, just with focus, depends on what is needed.


2. B. Yes Voigtlander makes such an adapter for Leica M on Sony A7, so just have patience and someone might make one and offer them online at some point in time, here a nice gentleman show it to you:


https://www.youtube.com/watch?v=fc5FqNIB5rc


3. Adapters usually don't have focusing build in, if your thinking using the new Nikon FTZ with an adapter, it will do absolutely no difference to your current Nikon D850 setup in any way or form regarding range or view.

Thanks EriK. I can always use a focus rail to focus, although that is second best to a helicoid. What I'm looking for, as you understand, is increase focus range for lenses like the Nikon "O."

[Erik Lund]

Exactly! 

[Akira]

So, I used the wrong term "wide view," when what I meant was range of focus. I use the Nikkor "O" CRT lens a lot, as well as many other "exotic" lenses, but the focus range often is very restricted. I would like to know what to ask for if I want the Nikkor "O" lens to have a larger focus range? Obviously, an adapter with a built-in helicoid that ranged from less than an F-Mount to the standard F-Mount would be perfect. However, would not adapters like 39-mm and M42 also do this? And I know that any change will mess with the optics to some degree, but with the Nikkor "O" (which already is gifted with strange optics) might not be worse for more focus range. I am just learning here.

BORG, a Japanese astronomical telescope manufacturer, makes thin adapters for mirrorless bodies of Sony, m4/3 and Nikon 1 with which you can set the lens closer than using the adapters with the "correct" registry.

https://www.tomytec.co.jp/borg/products/partsByC/14

I guess they would make similar adapters for Nikon Z or Canon EOS-R.  The adapter has the proprietary 49.8mm thread on the opposite side of the camera mount, but BORG also makes 49.8mm to 42mm adapter and 42mm to 39mm adapter.  So, you can attatch virtually any lenses.

The attached image is the m4/3 mount adapter.

[Erik Lund]

Yes and then just add a focusing helicoid (Also know as variable extension tube ) to that adapter

[Akira]

Yes and then just add a focusing helicoid (Also know as variable extension tube ) to that adapter

Also, you can simply omit the helicoid to maximize the focusing distance!

[Michael Erlewine]

Also, you can simply omit the helicoid to maximize the focusing distance!

And use a rail. That sounds good to me.