Hello,

I've got a Kodak lens Aero-Ektar f2,5 178 mm. I think it was used in Europe during WWII for aerian photography. I'm searching more informations about this lens (history, price, web links,...) Could you help me?

Sorry for my very bad English

François

-- François Renard (renard_fr@hotmail.com), January 16, 2002

Answers

Hello,

I can't contribute much information, but I know that this lens has been mentioned in the following web page as a lens that is subject to radioactivity:

http://people.smu.edu/rmonagha/mf/radioactive.html

I have also heard that this lens requires additional support when mounting due to its weight. It can put a lot of stress on the front standard of a camera.

You may also want to check out the "help" page on the Graflex website, as many Graflex members have posted questions/answers about the Aero Ektar:

www.graflex.org.

Best regards,

J. P. Mose

-- J. P. Mose (j.p.mose@lmco.com), January 16, 2002.

I have been researching the Aero-Ektars and have begun a web page with my findings: http://home.earthlink.net/~michaelbriggs/aeroektar/aeroektar.html

In brief, the fast Aero-Ektars were highly advanced lenses designed for night time aerial photography in WWII. One advanced technology was the use of newly developed high-index of refraction, low-dispersion glasses for two of the glass elements. These glasses intentionally incorporated the radioactive element Thorium.

Thorium has a very long half-life and relatively low level of radioactivity. Possession of Thorium containing optics is legal in the United States. Nevertheless, mimimizing ones exposure to radiation is wise and I suggest, when you are not using an Aero-Ektar, to store it far away (tens of feet) from people.

If you are interested in using a Aero-Ektar because of its very fast aperture (f2.5 in most versions), you might be disappointed. They no longer have the light gathering power expected from their fast apertures because some of the glass has turned brown. The browning is almost certainly due to self-induced radiation damage accumulated over the many years since their manufacture.

If any of you have an Aero-Ektar, I would like to receive via email the rim data, at least the focal length, aperture and serial number. This will help me determine the years of production and the numbers produced.

-- Michael Briggs (MichaelBriggs@earthlink.net), January 17, 2002.

I have several 178mm f2.5 Aero Ektars and the first one I bought came with a focussing mount, made to fit a Pentacon 6 camera. I have used them and they can give excellent results on 6x6cm. I have made an adaptor to try one on 5"x4" but I have not tried it yet.

I did have a 12" f2.5 for a while but it as so big and I could not use it so I sold it to a company that built special back-projection equipment for the London theatres. I guess it is being used still for this purpose.

My advice is make a simple mount and try it out - it makes a good portrait lens for 6x6.

The lens was built in large numbers in World War 2 to be fitted to a K24 camera which was an American copy of the British F24 camera. The K25 can be used with 5inch roll film but it requires 24volt power to operate the shutter properly. at least one shutter speed can be fired mechanically without power. The K25 was designed to use the 178mm lens as standard but there were other lenses - 5" wide angle and longer lenses too. the 12" f2.5 was built for a different much bigger 'night camera'

-- Tim Hicks (thickstp@aol.com), May 06, 2002.