135-mm Oxyplast lens

I inherited a large format lens marked as follows:

Oxyplast 1:4.5 f-135 mm L. O. Bittnet A.G. Munchen Doppel-Anastigmat

It's mounted in a dial-set Compur shutter, Serial Number 522465

Limited testing indicates it isn't very sharp.

Does anyone have any further information about this lens?

Gerry Ashton

"A" wrote in message
...
I inherited a large format lens marked as follows:

Oxyplast 1:4.5 f-135 mm L. O. Bittnet A.G. Munchen
Doppel-Anastigmat

It's mounted in a dial-set Compur shutter, Serial Number
522465

Limited testing indicates it isn't very sharp.

Does anyone have any further information about this lens?

Gerry Ashton

The dial set shutter is a very rough indication of age.
These were replaced with the "rim-set" Compur about 1930.
I'm sorry to say I have never heard of the manufacturer or
the lens before.
You may be able to discover its construction by looking
at the reflections of a small light source like a pencil
flashlight. Uncoated glass-air surfaces are very bright,
cemented surfaces are quite dim but visible. Look at each
cell from both sides. The name dopple anastigmat suggests
that it is a symmetrical lens, i.e., both cells the same.
The flashlight, with the aid of a magnifier will also show
up problems with any cemented surfaces. Shine the light
through the cells and look for any haziness, etc. Sometimes
apparent lack of sharpness is due to internal haze or
defective cement.
There appear to have been a number of lens makers in
Munich in the 1920's and before. Among them are Steinheil,
Rietzchel (became Agfa), Rodenstock, and Staeble. Staeble
used lens names similar to the above, that is, ending
in -plast, but not an Oxyplast, at least that I can find.


--
---
Richard Knoppow
Los Angeles, CA, USA

Gerry Ashton wrote:

I inherited a large format lens marked as follows:
Oxyplast 1:4.5 f-135 mm L. O. Bittnet A.G. Munchen Doppel-Anastigmat
It's mounted in a dial-set Compur shutter, Serial Number 522465
Limited testing indicates it isn't very sharp.
Does anyone have any further information about this lens?

Actually, the lens maker is L.O. Bittner of Munich. The dates of
manufacture for three designs of lenses they marketed range from
1919 to 1922, so the company wasn't around very long. The Oxyplast
is a 4/4 double anastigmat design, manufactured around 1922.
The coverage is 70 degrees, so it should provide moderate movement
on 4x5. The reference I have indicates that the lens may have been
supplied by Staeble. If it isn't "sharp", the elements may require
cleaning. Also, these lenses are best when stopped way down.

Michael, what is your source for the info? you seem to have data on
some pretty rare lenses (I was going to say obscure lenses but I don't
mean the pun).
By 4/4 do you mean 4 elements in each cell? Is this a variation of
the double Protar? The Protar patents would have been long expired in
1920.
f/4.5 is very fast for this type of lens. If it is a cemented
meniscus it probably suffers from the excessive zonal spherical
aberration typical of the type. At f/4.5 this would likely be quite
exagerated. Dagors and conertible Protars are sharp at around f/22 for
moderate coverage. If it isn't reasonably sharp stopped down I would
look for cement damage. A little oxidation around the edges doesn't
make a lot of difference but if the cement has become cloudy it would
make a mess of the image.
--
Richard Knoppow

Richard Knoppow wrote:

Michael, what is your source for the info? you seem to have data on
some pretty rare lenses (I was going to say obscure lenses but I don't
mean the pun).
By 4/4 do you mean 4 elements in each cell? Is this a variation of
the double Protar? The Protar patents would have been long expired in
1920.
f/4.5 is very fast for this type of lens. If it is a cemented
meniscus it probably suffers from the excessive zonal spherical
aberration typical of the type. At f/4.5 this would likely be quite
exagerated. Dagors and conertible Protars are sharp at around f/22 for
moderate coverage. If it isn't reasonably sharp stopped down I would
look for cement damage. A little oxidation around the edges doesn't
make a lot of difference but if the cement has become cloudy it would
make a mess of the image.

Hi!

The source was Hartmut Thiele's "150 Jahre Kameraoptik in Deutschland",
a trove of once obscure information.

By 4/4 I mean 4 elements in 4 groups, which was more or less of a simple
approach to wide angle lenses that most makers tweaked. The Oxyplast
is listed as a f/6.3 lens, however, the focal lengths range from 135 to
195 mm. A shutter for f/6.3 195 would give a speed of around 4.4 with
the shorter focal length if one assumes the shutter and not the cells
limit the aperture.

Bittner made other 4/4 lenses with similar specs that are listed as f/4.8,
f/5.4, f/6.3 with the same model name (Orthoklinar), focal length and year of
manufacture (1922), but suggested that the f/4.8 lens covered 75 deg and the 6.3
covered 70 deg. My guess is they used different shutters, and got less
vignetting with the fast shutter, and "improved" specs. In 1919 they made their
other model (LOB Ananstigmat; 4/4) with f/4.5 and f/5.5 apertures.

By the 1920's, designs were improving and without a presence in the marketplace
or R&D (can't find any lens patents for Bittner), they probably faded away quickly.

I have a similar Hekla 90mm f/6.8 4/4 doppel-anastigmat in a dial-set Compur
that was on an Ica folder. After cleaning it up, it covered 4x5 past the
movements of my Wista. The same lens is going on ebay for $0.77 (dagor77; item
7591597266). Unlike the Bittner, these are common and perhaps worth a couple
of dollars if someone's looking for an antique uncoated very flare-prone design.
A Dagor or Protar easily outperforms this lens.

"Michael Gudzinowicz" wrote in
message news:vykKf.3053$p13.2051@trnddc08...
Richard Knoppow wrote:

Michael, what is your source for the info? you seem
to have data on
some pretty rare lenses (I was going to say obscure
lenses but I don't
mean the pun).
By 4/4 do you mean 4 elements in each cell? Is this a
variation of
the double Protar? The Protar patents would have been
long expired in
1920.
f/4.5 is very fast for this type of lens. If it is a
cemented
meniscus it probably suffers from the excessive zonal
spherical
aberration typical of the type. At f/4.5 this would
likely be quite
exagerated. Dagors and conertible Protars are sharp at
around f/22 for
moderate coverage. If it isn't reasonably sharp stopped
down I would
look for cement damage. A little oxidation around the
edges doesn't
make a lot of difference but if the cement has become
cloudy it would
make a mess of the image.

Hi!

The source was Hartmut Thiele's "150 Jahre Kameraoptik in
Deutschland",
a trove of once obscure information.

By 4/4 I mean 4 elements in 4 groups, which was more or
less of a simple
approach to wide angle lenses that most makers tweaked.
The Oxyplast
is listed as a f/6.3 lens, however, the focal lengths
range from 135 to
195 mm. A shutter for f/6.3 195 would give a speed of
around 4.4 with
the shorter focal length if one assumes the shutter and
not the cells
limit the aperture.

Bittner made other 4/4 lenses with similar specs that are
listed as f/4.8, f/5.4, f/6.3 with the same model name
(Orthoklinar), focal length and year of manufacture
(1922), but suggested that the f/4.8 lens covered 75 deg
and the 6.3 covered 70 deg. My guess is they used
different shutters, and got less vignetting with the fast
shutter, and "improved" specs. In 1919 they made their
other model (LOB Ananstigmat; 4/4) with f/4.5 and f/5.5
apertures.

By the 1920's, designs were improving and without a
presence in the marketplace
or R&D (can't find any lens patents for Bittner), they
probably faded away quickly.

I have a similar Hekla 90mm f/6.8 4/4 doppel-anastigmat in
a dial-set Compur that was on an Ica folder. After
cleaning it up, it covered 4x5 past the movements of my
Wista. The same lens is going on ebay for $0.77 (dagor77;
item 7591597266). Unlike the Bittner, these are common and
perhaps worth a couple
of dollars if someone's looking for an antique uncoated
very flare-prone design.
A Dagor or Protar easily outperforms this lens.

For some reason, probably because it was 3AM, I didn't
recognize the standard nomenclature for lens construction.
Oh, dear. The lens soulds like the common double Gauss type
often used for wide angle lenses, for instance the Kodak
Wide Field Ektar. It may be that the particular lens is just
not a good example of the type, they are capable of very
good sharpness.
I looked up Hartmut Thiele, it looks like he has written
a number of interesting looking books, mostly on Zeiss
cameras and lenses. My German is sparce but I can make it
out with the aid of a dictionary. I think I will have to
aquire this book.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Michael Gudzinowicz" wrote in message
news:MJ9Kf.1680$0z.343@trnddc01...

Actually, the lens maker is L.O. Bittner of Munich. The dates of
manufacture for three designs of lenses they marketed range from
1919 to 1922, so the company wasn't around very long. The Oxyplast
is a 4/4 double anastigmat design, manufactured around 1922.
The coverage is 70 degrees, so it should provide moderate movement
on 4x5. The reference I have indicates that the lens may have been
supplied by Staeble. If it isn't "sharp", the elements may require
cleaning. Also, these lenses are best when stopped way down.

Thanks to Michael and Richard for the information. Indeed, I hit the wrong
key and the maker really is Bittner. The elements look good, and it's good
to know it should be a decent lens if stopped down enough.