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I am devoting a
few pages to off-the-beaten-track Ektars. The Ektars featured in this
section of the site are generally ones that were manufactured for Kodak
cameras or for other camera manufacturers. Of course Ektars in free-standing
shutters and barrels were purchased by other manufacturers of press
and view cameras, but Ektars also appeared on some non-Kodak cameras
with more complex mounts. Kodak also made Ektars for the military during
the '40s and '50s--most notably the Aero Ektar. In addition to general
aerial cameras and lenses, Kodak also made fire control and bombsight
optics Aero Ektars. Because of
the importance of the air campaign in WW II, military demand was created
for many kinds of photographic products, including lenses for aerial
photography. George Aklin, of the Kodak Optics department, developed
Gauss formulae for 7- and 12-inch high speed lenses called Aero Ektar's
that involved Kodak's first use of lanthanum crown glass. Here is the
patent There has been much speculation
about the radioactive measurements made from Aero Ektars. Both Lanthanum
glass used generally in the Aero Ektars and the rear element, containing
Thorium, are alleged to excite Geiger counters. The curator of the George
Eastman House has acknowledged significant radioactive emissions of
beta and gamma rays from Aero Ektars. There has been very active discussion
about the health risks posed by the use of Aero Ektars and the need
for care both in human exposure and to photographic materials. There
has been some post-9/11 speculation that, in shipment, these lenses
might trigger mail scanners designed to spot low-level nuclear sources,
causing such shipments to be confiscated. Some comment suggests that
the radioactivity may be caused by impurities in early glass compounds
and that lenses of specific brand and model may vary in their "hotness"
by batch of glass used. There have been reports of "hot" lenses
from this period that have been evaluated as dangerous by professionals
that monitor radioactive exposure. Other informed comment suggests that
there is little danger in typical use. Though there does not appear
to be agreement among experts, the cautious photographer will store
these lenses away from people, animals, plants and photosenitive stock.
Of the Kodak lenses the Aero Ektars appear to be the most likely to
cause problems, and while there are reports of other brands and models
of "hot" lenses, I haven't seen reports of other Ektars. Bob
Monaghan collected many posts about this phenomonon on his medium format
site, but the page has gone missing. Here is a link to my restoration
of that page Dr Michael Briggs, a NASA gamma-ray astrophysicist has done historical and empirical research on these lenses and has published his findings, by far the most authoritative source I have found on the Web. Particularly interesting are the myths he dispels about the radioactive characteristics of Aero Ektars. He has found Aero Ektars in the following lengths: 6-inch f/2.5 (all from 1955), 7-inch f/2.5, 12-inch f/2.5, 13.5-inch f/3.5, and 24-inch f/6.0. One aspect of Aero Ektars that Dr Briggs is following is the characteristic tint of the glass. While it may have had a yellow tint when new, Dr Briggs suspects that the radioactivity of the glass may have caused this tint to become browner. These lenses were made primarily for use with b&w infrared emulsions and the correction in color sensitivity may have taken into account their use at altitude with a design to minimize the effects of haze. Because of the large number of
Aero Ektars produced and their large maximum aperture, there is an active
interest in adapting them to non-aerial use. On the Gallery page, you
can see some of the kinds of mounts that have been adapted. Since the
Aero Ektar has no shutter and is a large lens a body with a focal plane
shutter is nearly essential, making Speed Graphics the most common platform
for the 7-inch version of this lens. There is just room on the 4x5 Graphic
lens board for a custom mount and the Graphic front standard seems sufficient
to handle the projection of the large front element. Here is a page
with links to the more extensive sites featuring this combination
Military Ektars. Several
Kodak cameras available on the consumer market were used by the military
during WW II. Kodak 35s had either Anastigmat or Anastigmat Special
lenses, the little brother of the Ektars. Some of these were made in
black for the military. The Medalist was used in large numbers by the
military because of its sturdy construction and excellent lens. Some
Medalists occasionally doubled for weapons--a three pound metal object
whirling around your head on a strong strap can be an effective way
to clear a path. I am not aware of a special military version of the
Medalist. Kodak's Graflex Division made Speed Graflexes with modifications
for the military and many of these came with Ektar lenses. The piece
de resistance of military Ektars was their use on the Combat Graphic
In the 1950s, Kodak made military versions of the Kodak Signet in olive and black. I am not aware of any other differences in the specs for these models besides external color and military model markings. Kardon. As the German sources
for precision miniatures became inaccessible in about 1940, the American
military began looking for domestic sources. One of the apocryphal stories
about the Kodak Ektra was that the military expected it to become the
American Leica/Contax. Kodak marketing plans certainly had commercial
Leica and the Contax sales in their competitive sights, and based on
Kodak's pride that the Navy had so quickly adopted the Medalist Hasselblad.
The original Hasselblad HK7 had a military connection; it was Victor
Hasselblad's improved version of a captured German surveillance camera
which he developed for the Swedish Air Force. When consumer Hasselblads
were first introduced in 1948, the lenses for the model 1600F were primarily
Kodak Ektars in the first Hasselblad mount. When Hasselblad produced
the improved 1000F
Television Ektanons.
Kodak made a series of television
lenses that were apparently used on broadcast and industrial cameras.
Some of these have mounts like the mount of the Ektra Ektars. There
may be specifications in Kodak and possibly RCA industrial catalogs
circa 1950 that would be interesting. Have an Ektar anomaly? Send me a description and an image, to the Comment? email address below, and I will add it to this page. |
![]() 10/25/2010 19:00 |
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