Any keen photographers on here?.. Camera lens mounts question..

[Zico]

Can anyone tell me which specific camera lens mounts (ie K-mount) can you get adapters for to fit to a C mount camera?


Im planning to build a Night vision spotter scope using a 3 stage cascade image intensifier tube from an Israeli tank periscope. It will be quite bulky and heavy but having 3 stages should be equal or at least very close to a Gen 3 scope in performance terms.. at a tiny fraction of the price.

My problem is that Im a bit thick and know very little about lenses/lens mounts. I'd like a decent level of magnification but I know I'll need quite a fast lens to let as much light in as possible.. unless of course I also get myself an IR laser.
I've been advised to use a C-mount on the scope due to it having a set focal distance I've seen a few nice lenses on Ebay that would do the job but not sure which lens mount types I'll be able to get adapters for..

Would it be possible to get a C mount adaptor for something like this?

http://www.ebay.co.uk/itm/CANON-FD-B...-/170834367826

[Zico]

Not even one view? You lot are useless.

[MrJan]

I hovered over the thread title, got the little pop up thing that has the first few lines of the post and realised that it was out of my depth

[Mark]

Yeah, lost me on the first line too.

I recently just use my iPhone camera on holiday instead of taking the proper camera and it worked just as well

[schmenke]

Yeah, lost me on the first line too.

I recently just use my iPhone camera on holiday instead of taking the proper camera and it worked just as well

No. Nothing beats a half-decent DSLR for image clarity, sharpness and view angle.

Although resolution of a phone camera may be comparable (I believe the iPhone 4S has 8MP), the individual pixel size is tiny. For example, a typical sensor size on a DSLR is ~ 20mm x 15mm the iPhone 4s is a mere 4.5mm x 3.4mm.
Similarly, the crop factor on a DSLR is ~1.5 whereas on the iPhone it's 7.6 .

Having said all that, I have no idea what Zico is on about :

[race aficionado]

My iPhone replaced my still & video cemera.
And it does so much more.
I don't leave home with out it.

*advert paid for by satisfied customer.


Sent from my iPhone

[D-Type]

Zico,
I'm too out of touch with modern kit to offer any useful advice. But reading your question, I wonder if you are confusing the 'male' and 'female' halves of a lens mount.

[Zico]

Zico,
I'm too out of touch with modern kit to offer any useful advice. But reading your question, I wonder if you are confusing the 'male' and 'female' halves of a lens mount.

I hope not.. but I dont know much about mounts so its very possible! I'll attempt to clarify.

I had been advised to use a C mount (used by the various old cini cameras) because the focal length (plane) from the lens (at the mount side) to the film (or NV tube in my case) is a known figure, a K, KA, M42 etc adaptor would then be fitted allowing the use of different lens types without me having to re-calculate and cut new shims for the NV tube position (if I upgraded with a lens which required a different mount) in the future.

I've actually since been advised to ignore the C mount + adaptor idea, to just work out the correct distance required for the M42 type mount and I'll still have a wide enough selection of cheap lenses to choose from... and this is what I now plan to do.

I've also found an American forum where quite a few have actually built their own DIY 3 stage cascade spotter scopes using the exact intensifier tube model I actually have. This has given me a lot of ideas (and advice on what not to do).
Some of the results these guys are getting with their homemade scopes in terms of performance is quite remarkable and actually pretty close to the Gen 3 scopes which cost between £3-5k new, not bad when it wont cost me more than £150 to make.. and that figure even includes a 300mw IR laser illuminator with a focusable beam.


See 14th post down on page 8 for single scene pictures/comparisons of the various generations of NV and the Cascade tube DIY NV scope (All pics were starlight, no moon, rural setting) here- DIY Cascade Tube Thread... - Page 8 - AR15.COM


I think I know where Im going with this now but thanks for the replies chaps... and if anyone else on here fancies making themselves one of these drop me a pm and I'll be happy to supply info, ideas and the best places to source the best components at the right prices.

[D-Type]

I think I understand now.

It used to be possible to get sets of M42 extension tubes (intended for close up photography). If you can get some, it may help to get the focal length right.

Come to think of it, bellows giving variable focus were also around and I think there was even a variable length extendable tube.

Another channel to explore might be bits for an enlarger. If I remember correctly, enlarger lenses use an M38 (Leica) thread.

[MrJan]

My iPhone replaced my still & video cemera.
And it does so much more.
I don't leave home with out it.

*advert paid for by satisfied customer.


Sent from my iPhone

I would suggest that your still camera wasn't up to much then : There's no way that I'd dream of replacing my DSLR with a phone camera, they just aren't up to the job, as Schmenke has already pointed out