This is topic Anamorphic Lenses ? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Al Chaney (Member # 794) on 03-22-2001, 12:46 PM:
I anve recently acquired a Century C projector. My throw distance is 33ft in a screening room 20 X 40. Can some tell me
what is the maximun widith I can get can and can I use my 16mm type "D" cinemascope Sankor lense on a 35mm projector?Thank Forum menbers
Al Chaney
Posted by Josh Jones (Member # 447) on 03-22-2001, 10:04 PM:
AFAIK, you picture width is a function of the prime lens, not the anamorphic. If you find out how tall the picture is in acadamy or 1.37:1, multiply that number times 2.37, and if your plate is cut properly, will give you your picture width. I could be wrong though. Anyone else?Josh
Posted by John Pytlak (Member # 331) on 03-22-2001, 10:16 PM:
Al:Check out the free Theatre Design Pro software available from Schneider Optics:
http://www.schneideroptics.com/theatre/desprodn.html
IscoOptic has a similar program called Cinema Lens Selector:
http://www.iscooptic.de/english.html
Not sure if a scope adapter designed for 16mm will adequately cover the full 35mm frame.
------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion
Posted by Brett Rankin (Member # 31) on 03-23-2001, 02:10 AM:
The 16-D probably won't be adequate unless your backup lens is of a very long focal length, like 5" (which, at 33 feet, will not produce a very big picture). You will get heavy vignetting in the corners, especially if you use such a large adapter that it acts as a barrel extender. Just find yourself a decent anamorphic lens designed for 35mm projection (older B&L's are cheap, and can be modified to focus down to 20 feet). The larger lens surface area will produce a sharper picture anyway.If you still want to use your 16-D, an adapter can be made out of various sizes of threaded PVC pipe to fit the different threading sizes on the two lenses.
Posted by Brad Miller (Member # 2) on 03-23-2001, 03:30 AM:
Go to the manuals download page here and download the Lens Calculator program. For quick and dirty calculations, it can't be beat. For more in depth calculations, go to www.schneideroptics.com and download their calculator.You will need "roughly" a 50mm prime lens for your anamorphic to get an "approximately" 12x28 foot image. (Must allow room for masking.) That will leave you needing "approximately" a 32mm lens for 1.85 flat. I wouldn't put any larger of a screen in that room, as you will be on the verge of having dark corners and focus issues.
Forget trying to use that 16mm lens.
Posted by Jeff Stricker (Member # 224) on 03-23-2001, 06:58 AM:
I have used a 16D mounted to a 3 1/2" prime lens without vignetting. The trick is to get it as close to the prime lens as possible. That's where I made some homebrew adapter parts! Of course, this is just fun home project 