On 2/5/2012 9:13 PM, Anthony Farr wrote:
On 6 February 2012 07:08, P. J. Alling<[email protected]> wrote:
The 150mm was not a popular focal length, (more expensive a 135, which
everyone and his brother just had to have and an odd icky focal length),
Interesting observation but beside the point to my little diatribe. The
popular focal lengths of lenses for 35mm photographers were a 50-58mm
"normal". (Not very normal, really since normal was a focal length
equal to the diagonal of the format. Most though not all other formats
normal lenses follow that general rule). A wide angle, usually 35mm in
focal length, primarily because anything wider began to be hideously
expensive, even in a bargain off brand, and for some reason not really
understood, the 135mm.
Now the father of a friend, who was an avid photographer, once told me
that when building my kit the first lenses I should get should be a wide
angle of about half my normal lens' focal length, and a telephoto of
about twice the normal lens' focal length. Not easy to do, given lens
prices and availability. Hell even being an engineer making a pretty
good wage, my friend's father couldn't really afford to follow his own
advice, he had a pretty extensive Minolta system built around a pair of
SRT 101 or 102 cameras, I don't remember which, and his widest angle
lens was a 35mm, though he had telephotos out to about 500mm.
Most 100-105mm lenses were fast and expensive, (2.8) was fast if you
didn't have a lot of money. A 135 in f3.5 with your camera makers brand
on it was almost affordable, a 135 at 2.8 with a Vivitar, Soligor,
Albanar, etc, name plate would probably be a bit less expensive than the
slower OEM, but those were your affordable choices.
The fact that everyone bought a 135mm as their first telephoto
reinforced that being the normal progression. Where that particular
focal length originated as a standard first telephoto doesn't matter.
The fact is that getting 100mm or 105mm meant you were rich, getting a
150mm meant you were rich and weird.
Well I happened to get a very good deal on a genuine Super Takumar 150mm
f4.0 and just bypassed the 135mm entirely, so I was just weird.
Back in the dawn of photography lenses were simpler beasts and cameras
all used plates or sheets of glass, copper, tin or paper, and later on
film. Many sizes were popular for various uses, see
http://en.wikipedia.org/wiki/Film_format#Single_image
It followed that many different lens focal lengths were required for
each format to have a normal lens that was the best natural performer
for that image size. To shoot longer or wider a photographer simply
fitted his camera with the normal lens of a larger or smaller camera.
Wide-angle shooting was a problem, because to make a smaller camera's
normal lens work well on a larger camera it needed to be stopped down
considerable, and still wasn't very good. Eventually the lens
designers got better at their craft and we got decent wide angle
lenses as well as long focus and portrait lenses that were specialized
to their tasks.
Which is all a long-winded way of saying that "odd icky focal
length(s)" are mostly the normal lenses of forgotten formats. 120mm
is the normal lens of a 3in x 4in camera. 135mm is the normal lens
of a quarter plate camera. 150mm is the normal lens of a postcard
camera. 135mm lingered as a popular focal length. And then someone
at Pentax felt a need to revive some less popular focal lengths, and
we got 120mm and 150mm Takumars and Pentaxes.
regards, Anthony
"Of what use is lens and light
to those who lack in mind and sight"
(Anon)
--
Don't lose heart! They might want to cut it out, and they'll want to avoid a
lengthily search.
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