Home
SearchSearch MemberlistMemberlist RegisterRegister ProfileProfile Log in to check your private messagesLog in to check your private messages Log inLog in

19mm thread diameter C mount or D mount cine lenses ??
View previous topic :: View next topic  


PostPosted: Tue Mar 12, 2013 7:30 pm    Post subject: 19mm thread diameter C mount or D mount cine lenses ?? Reply with quote

A friend convinced me to buy few old 8mm cine lenses and the first one worked out well. It fit the standard D mount to Pentax Q adapter without problem and made nice images.

However the following one did not work out. It is a Kinotel 1.5" f1.9 lenses and is supposed to be a C mount lens. It does have a C marked on the barrel.

It has too small of a thread diameter for the C adapter I have, and too large a diameter for a D mount. The rear element is larger than the other D mount lens I have.

The threading diameter measure 19mm (or very close to 19). Yet I haven't been able to find any information on the mounting and use of these lenses.

This lens is well made and can probably produce sharp image, but I hope I didn't end up with an overpriced paperweight.

Any help or info greatly appreciated.


PostPosted: Tue Mar 12, 2013 7:35 pm    Post subject: Reply with quote

C mounts are 25mm diameter, not sure what d mounts are, but a lot smaller.


PostPosted: Tue Mar 12, 2013 7:39 pm    Post subject: Reply with quote

iangreenhalgh1 wrote:
C mounts are 25mm diameter, not sure what d mounts are, but a lot smaller.


Right. I think D mount is 15 or so mm. So where does the 19mm fit in?


PostPosted: Tue Mar 12, 2013 8:57 pm    Post subject: Reply with quote

smallerlens wrote:
iangreenhalgh1 wrote:
C mounts are 25mm diameter, not sure what d mounts are, but a lot smaller.


Right. I think D mount is 15 or so mm. So where does the 19mm fit in?


To something else Smile I know Russian camera what has not standard screw mount.


PostPosted: Tue Mar 12, 2013 11:35 pm    Post subject: Reply with quote

Attila wrote:
smallerlens wrote:
iangreenhalgh1 wrote:
C mounts are 25mm diameter, not sure what d mounts are, but a lot smaller.


Right. I think D mount is 15 or so mm. So where does the 19mm fit in?


To something else Smile I know Russian camera what has not standard screw mount.


Yes, but the Kinotel lenses were made for the American market. They're all marked in English and I've seen them on old American-made movie cameras.


PostPosted: Thu Mar 14, 2013 1:20 am    Post subject: Reply with quote

just looked at a kinotel 1.5" 3.9 today and it fit my d mount adapter. same manufacturer, very similar build, slower lens, but a 15.88mm d mount thread.

are there 19mm d mount lens adapters out there? i couldn't find any.


PostPosted: Thu Mar 14, 2013 1:35 am    Post subject: Reply with quote

I also have a few 8mm cine gems by Yashica but I'm also not able to test them Sad
BTW: Does anyone know how to adapt the Zeiss Jena Biotar 12,5mm F2 (it has a bajonett for Pentaka 8 ) on Pentax Q?


Last edited by ForenSeil on Thu Mar 14, 2013 2:12 am; edited 1 time in total


PostPosted: Thu Mar 14, 2013 2:06 am    Post subject: Reply with quote

Kodak S mount maybe?


PostPosted: Thu Mar 14, 2013 2:15 am    Post subject: Reply with quote

Oh cr*p
http://www.ebay.de/itm/Adapter-for-Kodak-S-mount-Lenses-to-C-mount-1-/370702553765?pt=LH_DefaultDomain_0&hash=item564f9812a5
Prices for these adapters are almost insane


PostPosted: Thu Mar 14, 2013 2:27 am    Post subject: Reply with quote

iangreenhalgh1 wrote:
Kodak S mount maybe?


thanks for the suggestion. i just looked and the s mount is more complicated - not a simple bayonet.

i don't yet have a photo of the kinotel lens to post but it looks identical to a D or C mount other than the thread diameter.


PostPosted: Fri Aug 16, 2013 2:31 am    Post subject: Re: 19mm thread diameter C mount or D mount cine lenses ?? Reply with quote

smallerlens wrote:
A friend convinced me to buy few old 8mm cine lenses and the first one worked out well. It fit the standard D mount to Pentax Q adapter without problem and made nice images.

However the following one did not work out. It is a Kinotel 1.5" f1.9 lenses and is supposed to be a C mount lens. It does have a C marked on the barrel.

It has too small of a thread diameter for the C adapter I have, and too large a diameter for a D mount. The rear element is larger than the other D mount lens I have.

The threading diameter measure 19mm (or very close to 19). Yet I haven't been able to find any information on the mounting and use of these lenses.

This lens is well made and can probably produce sharp image, but I hope I didn't end up with an overpriced paperweight.

Any help or info greatly appreciated.


I think I have one with the same 19mm thread mount. Did you have any luck yet finding a way to adapt yours? Mine is a Cooke 1 1.2 inch Anastigmat f3.5. Beautiful lens, wish I could adapt it. I've got D mount adapters and C mount, and this mount it somewhere in between...


PostPosted: Fri Aug 16, 2013 2:48 am    Post subject: Re: 19mm thread diameter C mount or D mount cine lenses ?? Reply with quote

JimWoof wrote:
smallerlens wrote:
A friend convinced me to buy few old 8mm cine lenses and the first one worked out well. It fit the standard D mount to Pentax Q adapter without problem and made nice images.

However the following one did not work out. It is a Kinotel 1.5" f1.9 lenses and is supposed to be a C mount lens. It does have a C marked on the barrel.

It has too small of a thread diameter for the C adapter I have, and too large a diameter for a D mount. The rear element is larger than the other D mount lens I have.

The threading diameter measure 19mm (or very close to 19). Yet I haven't been able to find any information on the mounting and use of these lenses.

This lens is well made and can probably produce sharp image, but I hope I didn't end up with an overpriced paperweight.

Any help or info greatly appreciated.


I think I have one with the same 19mm thread mount. Did you have any luck yet finding a way to adapt yours? Mine is a Cooke 1 1.2 inch Anastigmat f3.5. Beautiful lens, wish I could adapt it. I've got D mount adapters and C mount, and this mount it somewhere in between...


unfortunately, no, but i was told by someone who was in the old movie camera business that the proper adapters exist. my guess is that very few if any are left since even the lenses and cameras of that era were considered worthless until only a short while ago. i'm going to keep looking. thanks for the response.


PostPosted: Mon Dec 15, 2014 11:37 pm    Post subject: d mount lens diameter Reply with quote

Its been over a year and I looked a number of times during that period but have been very frustrated that I can't use my nice shiny lens.

Here is an example on ebay of very similar lenses to mine, which is a Kinotel also.

Note that the description mentions the two different mount diameters of these lenses, 16.3mm and 18.9mm. Mine is about 18.9mm and from what I know the 16.3mm is the standard D mount diameter.

Had anyone seen adapter rings for these larger than D mount diameter lenses?

Thank you.


http://www.ebay.com/itm/Kino-Pair-2-5-8mm-Movie-Camera-Lenses-w-Case-/301326427175?pt=US_Vintage_Cameras&hash=item4628746427


PostPosted: Tue Dec 16, 2014 12:41 am    Post subject: Reply with quote

Ok, lets get the record straight:

D mount is 0.625 inches (about 15.8mm)
C mount is 1 inch - (about 25.4mm)
The lens mounts were created in inches so millimetre conversions are not exact.

OK.This lens is somewhere in between. Flange focal distance (ffd) is also an issue here. D mount is fixed at 12.29mm but C mount lenses can have a variety of ffd's depending how the lens was used and on what equipment. Can you calculate the ffd of your lens?

It would be very simple to make an adapter to fit your lens into a c-mount, but would it work?

Most C-mount adapters have an unspecified FFD. And unless you know what your ffd is, adapting it is like working in the dark. Too long and you'll only get macro, too short and your minimum focus may be infinity.

C on the lens may mean coated.


PostPosted: Tue Dec 16, 2014 1:31 am    Post subject: the record is straight... Reply with quote

But how to calculate ffd without mounting the lens?

Would it be simple to make a C - mount adapter? How?

Yes, its in between, but not the only one that is. I'm beginning to think that some of the old movie cameras had different diameter mounts. I just saw specs for one that has turret mounted lenses.


PostPosted: Tue Dec 16, 2014 9:01 pm    Post subject: Reply with quote

philslizzy wrote:
D mount is fixed at 12.29mm


Just a small intermezzo.
No, it isn't exactly so. Most (double)8mm-cameras follow this rule, but the wild ones exist. Ffd in d-mount for most 9.5mm cine-cameras is also a different story.


PostPosted: Tue Dec 16, 2014 11:34 pm    Post subject: Reply with quote

Gamera wrote:
philslizzy wrote:
D mount is fixed at 12.29mm


Just a small intermezzo.
No, it isn't exactly so. Most (double)8mm-cameras follow this rule, but the wild ones exist. Ffd in d-mount for most 9.5mm cine-cameras is also a different story.


Yes, of course I forgot the 9.5's. Thinking only about std8. 9.5mm came out 10 years earlier.
perhaps these lenses were made for Panoscope 16mm cameras or something as obscure.

To adapt: use a small worm of epoxy putty wrapped round the lens threads and more squeezed into the threads of the C-mount adaptor. Push the lens into the centre of the adaptor and press it firmly down onto a hard shiny plastic surface - a polythene bag is fine - to keep the lens and the adaptor square, Trim the excess putty off and let it set. This is a permanent solution. If you dont want to adapt it permanently brush a little oil onto the lens thread with a fine artist brush. When the putty is hard but not quite set, unscrew the lens just a little to break the seal then let it harden. At that point you can trim any that has spread out on the plastic bag. Wash the oil off the lens and adaptor. I use vegetable oil rather than machine oil of any type, it washes off with soapy water rather than solvents.

Epoxy putty: Click here to see on Ebay There are of course other makes, google it and find out what its called in your country.



I have done a similar adaptation with a small thread enlarger lens. I'll do another one and show photos

Of course if the ffd is different to the c-mount adaptor then yours will be useless. To find the ffd I suggest holding a fine millimetre ruler square against a block of something then aiming the lens at the sun and by moving the lens back and forth along the ruler watch the projected image on the block, you can see when the sun gets in focus. Then look where the lens mount is against the ruler. That should give your ffd. Not madly accurate but ball-park enough I think.


PostPosted: Thu Jan 15, 2015 10:15 am    Post subject: Reply with quote

Just read the whole thread. I think I know what is going on with the OP's lens (and the other one mentioned here). Taylor Hobson etc. had a system in some of their C-mount lenses which allowed 360 degree positioning of the lens barrell. The C-mount threaded piece is/was spring supported and mounted to the barrel with a somewhat conical locking piece which threaded to the lens. When everything is fine and clean the friction works as it should and pushing the lens towards the camera one could adjust the barrell in whichever position. The springy washers, C-mount piece and the locking piece are probably gone from OP's lens.
I think I have one of those somewhere but can not produce it now for pictures. It may even be the same lens.


PostPosted: Fri Jan 16, 2015 7:44 pm    Post subject: varying flange distance on Dmounts Reply with quote

" Flange focal distance (ffd) is also an issue here. D mount is fixed at 12.29mm but C mount lenses can have a variety of ffd's depending how the lens was used and on what equipment."

Usually, yes, but the first Bolex 2x8 , the L8 had a different Dmount flange distance of 7,8mm. An adapter ring was offered for those who wanted to use the later lenses.

p.


PostPosted: Sat Jan 17, 2015 1:30 am    Post subject: Reply with quote

so no nearer solving the mystery then.


PostPosted: Tue Feb 16, 2016 9:09 am    Post subject: Reply with quote

I happened upon this post randomly, and joined simply because I'm going through the exact same thing - but with an Ivotal 0.5" lens which was advertised as being D mount. After doing my own research and experimenting, I think it is a 19mm 0.7 pitch thread, I can confirm that in a few days when I get my adapter in the mail. The problem, however, is that the designed focal flange distance of this lens is NOT 0.69" (17.526mm) like C mount, but looks like it may be closer to or exactly 12.29mm of D mount - hard to say, because I was just checking infinity focus by manually moving the lens in / out of my naked camera body without mount adapter. When you seat it on the C mount adapter, it's like looking through a lens with a macro extension tube - so even if the thread adapter works, the lens itself is going to have very limited functionality. The difference in focal flange distance between C and D is about 5mm (5.236mm more or less exact) which also happens to be the difference between C and CS mount. In other words, the only cameras that this lens would seem to work with are CCTV cameras designed for industrial CS lenses (just like C mount but -5mm of flange distance) or one other interesting option, the GoPro equipped with the "Backbone" modification kits, which can natively support CS mount. This all seems like a lot of trouble to go through though, because with the 12.7mm focal length of the 0.5" and the 5.6x crop factor of the GoPro, you'll end up with a not so useful 71mm equivalent FOV whereas I have an Angenieux K3 9-36 zoom which is also f/1.4 and has a more useful equivalent focal length of 50-200, and although larger, is not really a "large" lens - so ultimately I feel like I have an Ivotal 0.5" which I'll never have a practical use for (and although I thought about the GoPro / Backbone combo for a bit, ultimately I don't think I'm going to go down that path). It would be even more sad if at the end of the day you couldn't achieve infinity focus because you were off by a fraction of a millimeter in the wrong direction.