OK! So forget about the zoom of course, but pick a 25mm with a modest aperture (1.8 or 2, even 2.8) I have a reference book that says it's best, so I repeat it...
Andre >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 >- >This message is from the Pentax-Discuss Mail List. To unsubscribe, >go to http://www.pdml.net and follow the directions. Don't forget to >visit the Pentax Users' Gallery at http://pug.komkon.org . -- - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
