8x10 Protar V lens

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I just picked up a lens with the following writing: Bausch & Lomb-Zeiss Protar, Series V Pat. Jan 13, 91. 8x10 2001790

My recollection is that Protar V lenses cover 110 degrees. Can anyone confirm? Does anyone have old literature stating what the exact focal length this lens is, or any other detailed info? I love to play with vintage lenses and like to find out what I can about their design, history, etc. I will be testing the lens soon and am expecting enormous coverage. The seller stated he thought the focal length was in the 210mm range, which would give this lens a shot at 8x20! Unfortunately, my current 8x20 project camera can't focus such a short lens at infinity. Time to rebuild.

-- Linas Kudzma (lkudzma@earthlink.net), May 24, 2002

Answers

The Protar V consists of 2 doublets in the front and the rear. The lens is a nice, sharp lens and is a backpackers dream, given how tiny it is, especially for the larger formats. Regarding coverage, the typical figures I have seen are 90 degrees which increases to about 100 degrees stopped down (think f/45) - the 110 degrees might be unlikley. The focal lengths recommended for 8x10 were the 180 and 210mm. I have a Zeiss issues of the 141mm which does cover 8x10, even wide open, although the fall off is pretty severe, and focussing at f/18 wide open can be challenging in dim light. So, I would think coverage on 8x20 would be marginal at best. Cheers, DJ

-- N Dhananjay (dhananjay-nayakankuppam@uiowa.edu), May 24, 2002.

Thanks for the info DJ. I did my first test of the lens this evening. I haven't developed the film yet, but on the GG it looked nice and sharp. Yes, a bit dim at f18, but I managed. I must have the 180mm, because I removed the Protar and popped my Fuji 210 on the camera and needed about an inch more extension to focus on the same scene.

This Protar V is an incredibly small lens to cover 8x10. Really remarkable.

-- Linas Kudzma (lkudzma@earthlink.net), May 24, 2002.


My 1928-29 Central Camera Company catalog lists 11 focal lengths for the B&L Series V f:18, from a 3 5/16" FL (covering 4X5 at f18) to a 37 1/4" FL (covering 20X25 inches at f18). The focal length given as covering 8X10 at f18 is 7 3/16" (or 183mm if my math is right). This is likely the FL you have. The catalog says "The angle of view of the image circle is about 110 degrees...". It doesn't say that coverage is at small f-stops, but I suspect it would only be achieved at f45 or so. If 110 degrees is true, I calculate an image circle for the 7 3/16" lens of 20.5". Which is pretty incredible, although probably not quite enough to cover 8X20 (I calculate the 8X20 diagonal to be 21.5", although the actual diagonal of an 8X20 holder is likely a little smaller than this.). If you are able to try your lens on 8X20, I'd love to hear what you find out. The next focal length listed is an 8 1/2" FL for 10X12 format. It probably has a much better chance of covering 8X20.

-- Leonard Robertson (leonard@harrington-wa.com), May 25, 2002.

Thanks for your answer Leonard. It certainly seems that my lens is approximately 180mm as it is a bit wider than my 210mm. I will try it on an 8x20 when I modify it for shorter focus. Even with the slightly too small circle and the light fall off I'd expect, it might make for an interesting ultra wide effect. In the meantime, it'll lighten my load when shooting 8x10. It's in a Volute shutter that is cranky and will need to be remounted into a modern shutter. Thanks again for the info.

-- Linas Kudzma (lkudzma@earthlink.net), May 25, 2002.

I took another look at the Central Camera catalog, and it shows all focal length Series V Protars as being available in either barrel mount or Volute shutter (even including the 37 1/4" FL). I have a vague memory of someone saying the Volute isn't such a bad shutter (if cleaned and lubed, of course). You might contact Mr. Grimes for his opinion on your Volute. The Central catalog has also lists Zeiss Jena Series V Protars, with focal lengths listed in both cm and inches. The inches FLs are slightly different than the ones given for the B&L Protars. The 7 3/16" B&L is a 18cm/7" in the Zeiss listing, and the coverage for the Zeiss is given as 6 1/2X8 1/2", while B&L claims 8X10 coverage. I suspect these are essentially the same lens with different labeling, but I'm not sure. Zeiss lists two shorter focal lengths that B&L doesn't - 4cm/1 1/2" and 6cm/2 1/2". I also have an 8X20 project pending - either an extension back for my 8X10 Eastman or an 8X20 box camera, but it is a "next winter" project. I look forward to hearing what you find out about using your Protar for 8X20. I would expect dark corners, but it might be something a person could live with (call it "artistic" if anyone objects to dark corners). In the meantime, I'll try my 5X7 Protar on 8X10 format. According to my calculations, it shouldn't quite cover, so the effect may be similar to using the 7 3/16" FL on 8X20. As for focusing at f18 in dim light, there is the trick of placing a flashlight or other bright bulb in the picture to focus on. It isn't really handy or fast, but it does work.

-- Leonard Robertson (leonard@harrington-wa.com), May 25, 2002.


Thanks again Leonard. The seller (this was Ebay) sent me a copy of an old B&L brochure that would seem to imply that this could be the 213mm Protar V. However the brochure is for barrel mount lenses, so may not apply exactly to my volute-shuttered example. The seller also said that mounted on a 12x20 camera this lens had a 20Ē circle of illumination. Itís most likely a 183mm Protar V. In any case, I plan to rebuild my 8x20 project later in the summer. Iíll let you know what kind of funky dark corner pictures I manage to take. Itíll be interesting. Dark corners donít bother many great ULF shooters, so it shouldnít bother me!

-- Linas Kudzma (lkudzma@compuserve.com), May 31, 2002.

Linas,

My 1907 Bausch and Lomb Catalog says the "Bausch & Lomb-Zeiss Series V Extreme Wide-Angle f-18" lens in the 8x10 size has a 7 and 3/16 inch focal length. The lens has a 9/16 inch diameter and cost 35$. Or 52$ in a shutter. The catalog says "This series is intended for the most exacting wide angle photography. It is the most desirable lens made for this purpose. The angle of view is 110 degrees."

My 6x8 protar v covers 8x10 with a smidgeon of movement, though the corners get pretty dark. The catalog lists the 6x8 as having a 5 9/16 inch focal length. The 10x12 has a 8 and 3/8 focal length.

-- Erik Ryberg (ryberg@seanet.com), May 31, 2002.


Great info from everyone! Thanks!

-- Linas Kudzma (lkudzma@compuserve.com), May 31, 2002.

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