Article View: sci.image.processing
Article #334Re: 1: 1 lens wanted
From: Alan Wm Paeth
Date: Thu, 13 Aug 1992 01:08
Date: Thu, 13 Aug 1992 01:08
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>In <1992Aug11.165800.8441@swift.cs.tcd.ie>, mahonj@swift.cs.tcd.ie writes: > Could anyone recommend a lens of about 50 mm focal length > optimised for 1:1 reproduction ratio ? Another approach -- buy a double-threaded 49mm (or 55mm or whatever) filter ring and attach two 50mm SLR lenses "head to head". This produces a symmetric 1:1 system that relays very flat, colour corrected image (24mm by 36mm format) onto the film plane. Such rings are made for this purpose -- they are NOT the same as reversing rings. Conventional C-mount or T-mount plumbing then puts the assembly on the video camera or SLR body. I would go with fast "prime" optics but would avoid using a superfast (f/1.2) aspheric objective. The slower stock 50mm lenses are increasingly easy to buy at camera shops -- many 35mm SLR buyers now opt for bodies only (so I guess they are "non-objective buyers" :-) ) and then add a zoom as their first lens. /Alan Paeth VE3AWP/KD3XG
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Newsgroups: sci.image.processing,rec.photo Path: arc1-ca.pugleaf.net!sparky!uunet!sun-barr!cs.utexas.edu!torn!watserv2.uwaterloo.ca!watmath!watcgl!watpix.uwaterloo.ca!awpaeth From: awpaeth@watpix.uwaterloo.ca (Alan Wm Paeth) Subject: Re: 1: 1 lens wanted Message-ID: <BswDux.AL3@watcgl.uwaterloo.ca> Sender: news@watcgl.uwaterloo.ca (USENET News System) Organization: University of Waterloo References: <1992Aug11.165800.8441@swift.cs.tcd.ie> <1992Aug12.094518@IASTATE.EDU> Date: Thu, 13 Aug 1992 01:08:56 GMT Lines: 18