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C-mount adaptor for M42 mount?


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#1 Matt Lazzarini

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Posted 04 April 2006 - 04:02 PM

Hi all,

I'm about to get my K-3 (fingers crossed that it works well) and was looking around for an adaptor that would let me use C-mount lenses on it (it's got the M42 mount). I know there are adaptors that go the other way, ie. an M42 lens on a c-mount cam, but I'm having a hard time finding what I'm looking for.

I did find this:

Borg C-Mount to M42 AD adaptor

" Borg C-Mount to M42 AD Adapter. Allows you to use a C-Mount lens (normally used with a 35mm SLR camera) with an M42P1 camera body.

Features:

* A Side: C-Mount Female
* B Side: M42 P1.0 Male

Light Path: 7mm"

An M42P1 camera body? Could this conceivably work with the K-3?
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#2 Charles MacDonald

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Posted 04 April 2006 - 09:44 PM

Hi all,
I'm about to get my K-3 (fingers crossed that it works well) and was looking around for an adaptor that would let me use C-mount lenses on it (it's got the M42 mount). I know there are adaptors that go the other way, ie. an M42 lens on a c-mount cam, but I'm having a hard time finding what I'm looking for.


Just rember two words..."Flange depth" :(

Check back to previous topics and you will find the exact figures but a c-mount lens expects to be about .650 inch away from the film or the vidicon... (or the CCD sensor these days) A Pentx M42 lens expects to be at least twice that distance away from the film. A K-3 uses the pentax lens at the same distance as it would be on a Pentax, a zenit or a prackika. At that distance a cmount lens would be set to focus VERY CLOSE even if the scale was set at infinity.

The fact that an adaptor is really only of use in close ups, or in mounting to telecopes and the like is why they are not offten seen. I do have an appaptor that lets a Pentax lens mount on a c-mount camera. but I have never really tried it becuase I am not sure how to aim a filmo under that condition.
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#3 dd3stp233

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Posted 04 April 2006 - 10:51 PM

FYI, the flange to film distance for an m42 Pentax mount is about 45.5mm.
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#4 monster vs robot

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Posted 04 April 2006 - 11:09 PM

A great guy who custom makes adaptors is Les Bosher in the UK-beautiful work and very reasonable compared to others. I believe he's at www.lesbosher.com

good luck
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#5 Bon Sawyer

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Posted 05 April 2006 - 09:10 AM

Allows you to use a C-Mount lens (normally used with a 35mm SLR camera) with an M42P1 camera body.

I guess there are some C-mount lenses out there that have a longer-than-normal flange focal distance. This would not include most of the ones you would likely want to use with the K3.

Bon
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#6 Leo Anthony Vale

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Posted 05 April 2006 - 02:34 PM

I guess there are some C-mount lenses out there that have a longer-than-normal flange focal distance. This would not include most of the ones you would likely want to use with the K3.


---In which case they wouldn't be Cmts, rather they'd be 1"x32tpi threaded lenses.

That adaptor is astronomical not photographic and is for mounting an SLR camera on a telescope.

The ring could be used for micro photography.
I think displacing the lens twice the focal length will give a 1:1 image.
45.5-17.5=25 +7=32; so a 16mm on that ring will give a good close up of a bee's head' if you can get her to stand still.

---LV
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#7 Leo Anthony Vale

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Posted 05 April 2006 - 03:03 PM

I'm about to get my K-3 (fingers crossed that it works well) and was looking around for an adaptor that would let me use C-mount lenses on it (it's got the M42 mount). I know there are adaptors that go the other way, ie. an M42 lens on a c-mount cam, but I'm having a hard time finding what I'm looking for.


---And how often has this same question been asked?
& the Nikon to M42 variation?


Here's a useful link:

http://www.a1.nl/pho...rink/mounts.htm

Read the text too.

Also:

http://rondexter.com..._dimensions.htm

http://rondexter.com...ns_adapters.htm

---LV
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