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Michael Snyder
4-Dec-1999, 10:11
Does anyone have a reference source for Ross lenses, in particular the telephoto types? Have been searching the web and the 4 to 11 listings are of no particula r help. Thank you.

Michael Phifer
10-Dec-1999, 16:41
Mike, Ihave an old reference (Berfore Web). I hope it is what you are loking for . From the 1939 Handbook of Photography, Henny and Dudley, McGraw - Hill, 1939. (A great Reference by the way)

Ross, Ltd. Clapham Common, London S.W.4., England, had two brands of Telephoto l enses The Teleros, and the Telecentric. All (but the f6.3 Teleros) were 2X tele' s (the back focus (the distance from rear Glass to Focus Plane, i.e. Bellows dra w) is half the focal length. They had about 30 degrees of coverage. The f 6.3 Te leros had only 18 degrees of coverage and was a 3x tele....

Hope this helps...

Michael Phifer
12-Dec-1999, 16:41
Michael, Getting back to you on "How Good are they?" I do not have first hand kn owledge of their performance. However, from the looks of the cut away views, the y have the potential to make very fine images. Both are five element lenses. The Teleros design consists of a cemented Double on the front positive, and a cemen ted Tripple on the rear negative. The Telecentric the Tripple is on the Positive .

Contrast should be good, since only four Glass/Air surfaces are involved..... Mi ke

patrickth
25-Aug-2010, 16:32
I know this is an old thread, but just found a Ross Teleros 5.5- f32 17" in my stash and wondering if anyone can translate that as to how long it will be on my 4x5. It is in barrel, and I was thinking I might be able to mount it in a packard shutter i have somewhere.

Is it worth it? Any opinions?

Brian Stein
25-Aug-2010, 18:14
focal length will be 17" but it from the above info it will focus at about 12" of bellows draw (the advantage of the telephoto construction). No idea about quality etc

patrickth
25-Aug-2010, 18:29
focal length will be 17" but it from the above info it will focus at about 12" of bellows draw (the advantage of the telephoto construction). No idea about quality etc

Thanks. Guess I will have to just see how it goes.