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Kodak Anastigmat lenses began appearing
about 1915. Many of the Kodak advanced amateur cameras of this period
could be purchased with any of several lenses fitted, including the Goerz
Dagor f /6.8, Bausch & Lomb Plastigmat f /6.8, Bausch
& Lomb Zeiss Tessar f /6.3, Cooke Anastigmat f /6.5,
as well as the Zeiss Kodak Anastigmat f /6.3 and the Kodak Anastigmat
f /7.7. Increasingly through the 1920's and 1930s, Kodak installed
lenses of its own manufacture on its cameras. Most of the 616 and 620
folders of the 1930s had Kodak Anastigmats with maximum apertures of f /7.7,
f /6.3, f /5.6, or f /4.5; and most
of the Anastigmats on Kodak amateur cameras of the 1930s were modeled
after the Cooke air-spaced triplet. In general, Kodak never followed the
European tradition of naming its lenses for the optical formula and in
the early 1930s most of the quality amateur lenses were simply "Anastigmats."
As Kodak expanded its lens lines, it also created new names for lens lines
to describe relative quality and special performance characteristics.
The last half of the 1930s was a
time of investment at Kodak in new designs and manufacturing. In the 1940s,
as consumer supply was usurped by war time needs, defense requirements
spurred new developments. Consumer and professional lens introduction
in early postwar years capitalized on these developments. Thus there was
continual improvement in Kodak lenses in design and in quality control
from the mid-30s to the early 50s. This makes tracing actual lens design
difficult in retrospect. Rudolf Kingslake was appointed head of Kodak
optics in 1939 on the retirement of C. W. Frederick and an early achievement
was the publication in 1940 of the Kodak Reference Manual containing detailed
technical specifications of Kodak lenses. While there are production departures
from what is documented in the Manual, its information and information
that has appeared in the successor, Kodak Data Books, has made
research into Kodak lens design much easier for collectors. An additional
source of documentation about Kodak optical design, though not production
varients, are patent records .
By the mid-30s, two developments
changed the direction of Kodak optics--the exploitation by German camera
makers of 35mm film stock and the development of color emulsions. Miniature
cameras from Europe--primarily Leica and Contax--were being offered with
much faster lenses, so shortly after Kodak introduced the Retina in 1934
and the Bantam cameras in 1935, the top models of those cameras had a
new model of Kodak lens--the Ektar. Initially the fastest Retina Ektars
were f /3.5, while
the "Anastigmat Ektar" on the Bantam Special was f /2.0
of a Biotar design. In the Ektar line, Kodak began to apply its research
about the effects of lateral color aberration, particularly on newly released
color emulsions. These new lenses employed new glasses that Kodak developed
and in addition to lateral color correction, other aberrations were also
minimized. The least expensive
Bantams received the nondescript "Kodalinear" f /8.0,
while the next model had the Anastigmat f /6.3 triplet. The
model just below the Bantam Special got a new Tessar type lens--the Kodak
Anastigmat Special 47mm f /4.5. The maximum aperture of this
lens was increased to f /3.5 in 1938 for Kodak's first entry
into the domestic 35mm market--the Kodak 35. Cheaper versions of the Kodak
35 had f /4.5 and f /5.6 triplets as Kodak Anastigmats.
In 1937, a new set of Kodak advanced
folders for 616 and 620 film debuted--the Vigilants, Monitors, Seniors
and Specials--that had either the f /6.3 Anastigmat triplet
or a new Tessar-design f /4.5 Anastigmat Special. This brought
a new quality level to what would become known as "medium format."
It also preceded by four years, the introduction of the first medium format
Ektar on the 1941 Medalist. You can compare Kodak Anastigmat Special (Anastar)
and Ektar design on a page
with cutaway photographs. There were also Tessar-design Anastigmats in
103mm and 126mm lengths, that in their general documented structure were
indistinguishable from the 100mm, 101mm and 127mm Anastigmat Specials.
This similarity in the Kodak documentation raises some obvious questions.
Was the quality of all Anastigmats the same over the course of their existence
and over all of Kodak's product lines? Was an f /6.3 Anastigmat
triplet on a Kodak Senior the equivalent to an 7 1/2-inch
Anastigmat Tessar design in an Ilex shutter to be used on a view camera
and costing several times more than the Senior. Intuitively, we would
probably expect the larger lens to be better in some ways. Countering
that intuition is that the Senior lens was made in much larger numbers,
bringing down the unit costs dramatically. Chris Perez's resolution tests
for an uncoated Anastigmat Special used on the Kodak Special Six-20 shows
just how good some of these folder lenses were. Also consider that each
lens was designed independently and glasses were selected to meet the
particular optical needs of a given focal length, aperture and lens design.
Some designs are inherently more successful than others. Product lines
run their course and new materials--glasses, coatings--designs and manufacturing
techniques intersect product lines at different points in their maturity.
In the 1948 Data Book, Kodak recognizes
a naming change with this announcement:

Professional quality Kodak lenses
were available from a pre-1940 date as Kodak Anastigmats. These were all
Tessar designs with a maximum aperture of f /4.5, except for
the No. 70 Kodak Anastigmat f /7.7 8-inch, which was a Dialyte
design. These were offered in 5 1/2, 6
3/8, 71/2,
8 1/2, 10 and
12 inch in barrels and shutters and were numbered No 21 through No 36.
The 1948 Data Book reflects Kodak's single-coating (Lumenizing) process
throughout its lines of lenses, synchronized shutters and a revamping
of professional lenses. The Wide Field Ektar series was introduced; new
127mm and 152mm Ektars were added as new Tessar designs. All of the Anastigmats,
except the f /7.7 8-inch, were retired and the Eastman Ektars
became the Commercial Ektar line of f /6.3 lenses in 8 1/2-inch,
10-inch, 12-inch and 14-inch lengths. Commercial Ektars are Tessar designs,
but have improved performance because of the smaller maximum aperture.
Not everything in production is as it appeared in the data books, since
I have two 7 1/2-inch Lumenized Ektars in Ilex
shutters--one made in 1948 and another manufactured in 1965. Scans of
information about professional lenses is shown here .
In enlarger lenses, Kodak followed
a similar strategy. In the late 30s and early 40s, there were both Projection
Anastigmats and Projection Ektars, with the latter having better color
correction. By the end of the decade, the lower quality lenses were called
Ektanons and the best corrected lenses were Ektars, with the Ektars being
limited to the 2-inch to 4-inch range.
So, while the overall quality of
Kodak lenses improved significantly over the period 1935 to 1950, Kodak
established and maintained the following lines which differentiated relative
quality at given production points:
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