I have a lot of older equipment which allow the use of prime lenses. Many of these have commercial names. For example, my Kodak Medalist I rangefinder camera from the 1940's has a f3.5 100mm Ektar lens. From what I can gather, this lens is a Tessar design. I just got a Zeiss Planar taken from a Graphlex XLRF. Apparently this design goes back to the early decades of this century.

My question is this: Does anyone know of a reference which explains these designs. I have "A User's Guide to the View Camera by Jim Stone. This books does delve into the subject of lens design and history, but I would like to go a tad further.

Any help will be appreciated.

Bruce Karnopp

-- Bruce Karnopp (karnopp@engin.umich.edu), November 02, 2000

Answers

There is a series of books by, I believe, Kingslake, who covers lens designs better than anyone. The Focal Encyc. of Photography also has a good lens design section. I have a 1939 copy of Kodak "Lenses & Shutters" but it doesn't have the 100mm f/3.5. It does have a 107mm f/3.7 Ektar used on Speed Graphics and the like. The 100 might be a close relative.

-- Conrad Hoffman (choffman@rpa.net), November 02, 2000.

Bruce, I think the book series Conrad referred to was called "Optical Engineering", and something like the first five or six volumes (around 1965 to 1970?) were edited by Kingslake. My fuzzy recollection is that one of them had a section on camera lens types actually written by Kingslake. Libraries are probably your only chance of finding these today!

Kingslake also wrote a book, "The History of the Photographic Lens" which is available from Amazon: http://www.amazon.com/exec/obidos/ASIN/0124086403/qid=973212113/sr=1-1 /002-7973314-7878404

I paged through a copy about 10 years ago; my memory is really fuzzy on this, but I think it might have been like an extended version of the Optical Engineering section. It might be just what you're looking for. Can anyone else comment on this book?

PS, FWIW I believe the Zeiss Planar was designed in the late 1890s by Rudolph; my understanding is that it was not feasible until years later when anti-reflection coatings came into use.

-- Bill C (bcarriel@cpicorp.com), November 02, 2000.

A more concise, (and cheaper!) version of the information you want is probably contained in the extensive appendix to Arthur Cox's "Photographic Optics", Focal Press. This shows elementary diagrams of several hundred different lenses, divided into type and application, and also gives some useful data, such as angle of view. The text also gives a potted history of lens development.
Unfortunately, I believe both Kingslake and Cox are now out of print, but Cox's work is reasonbly common secondhand and in public libraries.

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 03, 2000.

The Kodak Ektar 100mm/f:3.5 on the Medalist is a Heliar design (five elements, three groups). I've adapted one for 35mm use and like it quite a lot.

On the Medalist, see:

http://www.smu.edu/~rmonagha/mf/kodakmedalist.html

On my adaptation, see:

http://www.smu.edu/~rmonagha/mf/medalist/

-- David Goldfarb (dgoldfarb@barnard.edu), November 03, 2000.

Bruce, Tessar and Planar were both designed by Carl Zeiss lens designer Paul Rudolph, Planar in 1896 and Tessar in 1902. Tessar is a four element three group design. Some Tessar lenses are focused by rotating the front element, better ones are focused by moving the whole lens.

1896 Zeiss Planar was a 6 element 4 group double Gauss type design.

-- martin tai (martin.tai@capcanada.com), November 04, 2000.

Yes, the first Planar was a symmetric lens, much different than the Planar on the Rolleiflexes and the Hasselblad/Rollei slr cameras.

-- Patric (jenspatric@mail.bip.net), November 05, 2000.