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-   -   Cylinder Lenses (https://www.dvinfo.net/forum/alternative-imaging-methods/37735-cylinder-lenses.html)

Keith Kline January 13th, 2005 06:02 PM

Cylinder Lenses
 
i was reading some of the posts before about using a cylinder lens to create anamorphic footage. Has anyone made any progress in this? I'm curious if anyone has the anamorphic adapter for the Panasonic or has access to one. I've looked at some pictures online, but I can't tell if it's just a single lens mounted in a housing or if it's multiple lenses. I'm interested in experimenting with a cylinder lens, but I can't figure out if there is a way to calculate the magnification factor of a cylinder lens. Anyone have any ideas?

Aaron Shaw January 13th, 2005 07:21 PM

Hi Keith,

I've been experimenting around with this sort of idea in conjunction with a mini35 type system. In my case I am trying to build a rear anamorphic adapter which eleminates some of the problems that normal adapters have.

The panasonic is almost certainly a multi element lens to help correct for abberation.

Will post more on the magnification factor in a bit

Keith Kline January 13th, 2005 09:35 PM

That's actually what I was interested in the cylinder lens for. I am attepting a rotating GG for my XL1s, but I'd like to be able to figure out a way to make it anamorphic. Do you have any idea on what the others lenses in the panasonic adapter might be? Thanks.

Aaron Shaw January 13th, 2005 09:42 PM

Still need to dig up my info on the magnification factor. Will post when I have everything I found collected.

Regarding the panasonic lens: I'm fairly sure it uses both a convex and a concave lens element. Whether there is anything additionally I do not know.

Elements such as these:

http://www.optosigma.com/miva/merchant.mv?Screen=PROD&Store_Code=OS&Product_Code=pg93-95
http://www.optosigma.com/miva/merchant.mv?Screen=PROD&Store_Code=OS&Product_Code=pg88-92

Where did you pick up your lens?

An interesting way to get the necessary optics for cheap would be to buy an anamorphic projector lens which you could hack up and experiment with. That's what I am planning on trying next. Once I get everything figured out I'll probably order coated elements from optosigma.

Keith Kline January 13th, 2005 10:07 PM

I actually haven't picked up a lens yet. I emailed several companies and I didn't hear back from several and the ones I did hear back from couldn't tell me anything I needed to know. Ideally I'd like to figure out a way to get it (at least close) to a standard ratio like 1.78 to 1 or even 2.31 to one, although I'm not sure how well that would work on a mini DV camera. Even if it was close it might even be possible to crop part of the image to fit one of the standard ratios better.

Valeriu Campan January 13th, 2005 11:21 PM

You can pick a number of rear anamorphic adapters from ebay, especially russian made ones. I have used some for 35mm motion picture and they come with lots of problems like abberations, focus issues, loss of light ... You need to stop down the take up lens at least 2 stops from the max apperture to compensate for some of the problems mentioned above.
A better solution would be to use a "all in one" rectangular or spherical anamorphic lens. Some of the russian LOMO or Ekran are not too bad. Use them with a PL>XL1 lens adapter.

Aaron Shaw January 14th, 2005 12:01 PM

Not sure what you mean by all in one. Are you just talking about a true anamorphic 35mm lens? Problem is these things are very costly...

Rear anamorphics shouldn't cause the problems you refer to. That sounds more like an anamorphic adapter. I've looked on ebay and haven't ever seen a rear anamorphic system. They have plenty of anamorphic projector lenses though which some people use in conjunction with 35mm lenses. This is, however, a very different thing.

Keith Kline January 14th, 2005 12:46 PM

The only things I've come across so far are the panasonic adapter and the ones on ebay, anamorpic projector lenses. That's why I the talk on here before sparked my interests in cylinder lenses. I know the larger cylinder lenses aren't cheap, but they are alot more reasonable than the panasonic adapter. Maybe if we could figure out the lenses used it that then figured out a way to mount them in front of the prime lens.

Brett Erskine January 14th, 2005 02:34 PM

According to my math if you want to have a 2.35 image anamorphically squeezed to fit on a standard video CCD then you will need to use something stronger than the Panasonics anamorphic adapter (1.33X). The special anamorphic lens that will do this will be 1.78X. Bad news because they are rare but they do exist. I even remember seeing some photo lenses that did this. There are also some film projector anamorphic lenses as well that are 1.78X. I also recall seeing anamorphic lenses available for video projectors. Once again a rare/specialty item but they may be 1.78X because they are intended for video. I wish I had direct links for you. I can tell you I found them on a google search.

Keith Kline January 14th, 2005 04:55 PM

<<<-- Originally posted by Brett Erskine : According to my math if you want to have a 2.35 image anamorphically squeezed to fit on a standard video CCD then you will need to use something stronger than the Panasonics anamorphic adapter (1.33X). The special anamorphic lens that will do this will be 1.78X. Bad news because they are rare but they do exist. I even remember seeing some photo lenses that did this. There are also some film projector anamorphic lenses as well that are 1.78X. I also recall seeing anamorphic lenses available for video projectors. Once again a rare/specialty item but they may be 1.78X because they are intended for video. I wish I had direct links for you. I can tell you I found them on a google search. -->>>

Acutally I wouldn't even mind a 1.33x squeeze at all. I guess it's the diy and/or cheap nature in me that was trying to find a cheaper way to get it than the panasonic adapter. That's why the talk of cylinder lenses appealed to me. I just haven't been able to find out if there is a way to calcuale the magnification across one or not.


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