Andre,
Actually, the lens I have is a zoom, it's a 3.3mm - 8mm zoom. (VERY
wide). It's an f1.4 lens.
Thanks for the info on reversing a c-mount lens. I'll have to try
it sometimes soon. I have a couple of spare 25 mm lenses, just need to
select an appropriate one, and sacrifice a lens and body cap. One
question: What size hole to drill? Do you remove the entire cover from
the lenscap?
When you get some good results from your lens, let us all know.
andre wrote:
> Bill, you have a 8mm lens f3.3 and a C-mount camera? I was talking
> about putting cine lenses reversed on 35mm and larger cameras. It may
> still interest you (and others) to get some details on home-made adapters.
>
> But first of all, to do some nice macro, the preferred focal is the
> normal one (around 25mm for C-mount and 13mm for 8mm). Your 8mm is wide
> angle and not recommended. I guess a slight tele like 36mm in C-mount
> would also work fine with a bit less magnification. I'll experiment
> with this in september or later and eventually post more details.
>
> For the reversed adapter, you ask a machinist to make a hole in the cap
> of the cine lens (you need it!), you glue it with epoxy in the center of
> a 42mm plastic body cap that has a hole the same dimension and voila!
> You have a home-made reverse adapter for lenses with this odd filter
> size. You need to put the adapter on a screw mount bellows or tube (or
> any bellows that take a screw adapter).
>
> But first you have to find a good cine lens.
>
> Andre
>
>> Andre,
>>
>> Interesting idea! I never though of putting one of these lenses
>> reversed on ANYTHING, much less a 6x7. Let me know how your homemade
>> adapter works, I'd definitly be interested.
>>
>> It's definitly a C mount lens, and a C mount camera. No way to change
>> lens flange or anything.
>>
> The lens in question is a 3.3-8 mm lens. I am now BELIEVE that the lens
> is meant to mount close to some other ocular device; such as a
> microscope or telescope. I'm going to put it away for further use later.
> IL Bill
>
>
> andre wrote:
>
>>> By the way, it may interest you to know that you can use 8mm and 16mm
>>> cine lenses REVERSED for Triple-X macros (the pun is for
>>> lilliputians). I mean 3X and over. If this is the case, you can vary
>>> the distance of the lens from the film plane with a bellow (and
>>> easily cover full frame on a Pentax 67), but the distance of the
>>> subject to the front of the lens (well... we could say the back as
>>> the lens is reversed) should not go over the distance between a 16mm
>>> cine lens and the 16mm film in a 16mm camera. This if you want the
>>> best optical quality.
>>>
>>> I don't know if this is clear... and if it may interest some
>>> PDMLers. I've got the theory (some...), I've acquired a few lenses
>>> recently, I'm actually working on some home-made adapters... the
>>> practice will follow within a few months I hope.
>>>
>>> Andre
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