Caltar 210mm info needed

Hi all:

Anyone out there know anything about older Caltar lenses?
There's a 210mm f 5.6 in very good condition I could buy.
However, though Calumet says this lens (it a "Calumet
Caltar-S II") was made by Schneider probably in the late
1970s (it's multicoated) they had no other info to offer
and there is no serial number on the lens.

I was interested in determining the age of the lens, the
specifications for this lens, optics and optical quality,
how it compared with a similar 210mm Symmar lens, etc. I'm
also baffled as to why Schneider included no serial number on
this or other Caltar lenses of the time, since newer Caltars
(made by Rodenstock) all have serial numbers.


TIA

Tom Phillips

Tom Phillips wrote in :

Hi all:

Anyone out there know anything about older Caltar lenses?
There's a 210mm f 5.6 in very good condition I could buy.
However, though Calumet says this lens (it a "Calumet
Caltar-S II") was made by Schneider probably in the late
1970s (it's multicoated) they had no other info to offer
and there is no serial number on the lens.

I was interested in determining the age of the lens, the
specifications for this lens, optics and optical quality,
how it compared with a similar 210mm Symmar lens, etc. I'm
also baffled as to why Schneider included no serial number on
this or other Caltar lenses of the time, since newer Caltars
(made by Rodenstock) all have serial numbers.


TIA

Tom Phillips


Tom -

Kerry Thalmann had an article in View Camera last year on the history of
Caltar lenses. He included a table for the 1976-83 Caltar S series of
lenses in which he described the 210mm f5.6 as 6 elements in 4 groups, 70
deg angle of coverage, 294mm image circle, Copal 1 shutter, and requiring
a 77mm filter. Made by Schneider. In the text, he noted that the lenses
in the series were initially single coated, but started double coating in
1977, and the double coated lenses are all marked "multicoated". He also
said "performance of these lenses is quite excellent - identical in all
respects to Schneider's own Super Angulon and Symmar-S offerings at that
time". But he also noted that these are Schneider lenses and display the
typical Schneider problem of bubbles in the blackening between lens
elements and barrels.

Louie Powell wrote:

Tom Phillips wrote in :

Hi all:

Anyone out there know anything about older Caltar lenses?
There's a 210mm f 5.6 in very good condition I could buy.
However, though Calumet says this lens (it a "Calumet
Caltar-S II") was made by Schneider probably in the late
1970s (it's multicoated) they had no other info to offer
and there is no serial number on the lens.

I was interested in determining the age of the lens, the
specifications for this lens, optics and optical quality,
how it compared with a similar 210mm Symmar lens, etc. I'm
also baffled as to why Schneider included no serial number on
this or other Caltar lenses of the time, since newer Caltars
(made by Rodenstock) all have serial numbers.


TIA

Tom Phillips


Tom -

Kerry Thalmann had an article in View Camera last year on the history of
Caltar lenses. He included a table for the 1976-83 Caltar S series of
lenses in which he described the 210mm f5.6 as 6 elements in 4 groups, 70
deg angle of coverage, 294mm image circle, Copal 1 shutter, and requiring
a 77mm filter. Made by Schneider. In the text, he noted that the lenses
in the series were initially single coated, but started double coating in
1977, and the double coated lenses are all marked "multicoated". He also
said "performance of these lenses is quite excellent - identical in all
respects to Schneider's own Super Angulon and Symmar-S offerings at that
time". But he also noted that these are Schneider lenses and display the
typical Schneider problem of bubbles in the blackening between lens
elements and barrels.

Outstanding reply/info. Thanks. Guess I should subscribe
to View Camera :-) I'm not familiar with the bubble issue.

Also, would you happen to know the particular issue? If not
perhaps largformat does...

In article ,
Louie Powell wrote:

Tom Phillips wrote in :

Hi all:

Anyone out there know anything about older Caltar lenses?
There's a 210mm f 5.6 in very good condition I could buy.
However, though Calumet says this lens (it a "Calumet
Caltar-S II") was made by Schneider probably in the late
1970s (it's multicoated) they had no other info to offer
and there is no serial number on the lens.

I was interested in determining the age of the lens, the
specifications for this lens, optics and optical quality,
how it compared with a similar 210mm Symmar lens, etc. I'm
also baffled as to why Schneider included no serial number on
this or other Caltar lenses of the time, since newer Caltars
(made by Rodenstock) all have serial numbers.


TIA

Tom Phillips


Tom -

Kerry Thalmann had an article in View Camera last year on the history of
Caltar lenses. He included a table for the 1976-83 Caltar S series of
lenses in which he described the 210mm f5.6 as 6 elements in 4 groups, 70
deg angle of coverage, 294mm image circle, Copal 1 shutter, and requiring
a 77mm filter. Made by Schneider. In the text, he noted that the lenses
in the series were initially single coated, but started double coating in
1977, and the double coated lenses are all marked "multicoated". He also
said "performance of these lenses is quite excellent - identical in all
respects to Schneider's own Super Angulon and Symmar-S offerings at that
time". But he also noted that these are Schneider lenses and display the
typical Schneider problem of bubbles in the blackening between lens
elements and barrels.

I have a Schneider lens with those bubbles. Has it ever been determined
what that is and does it eventually create a problem?

Claude

But he also noted that these are Schneider lenses and display the
typical Schneider problem of bubbles in the blackening between lens
elements and barrels.

I've often wondered, why is this problem so common in Schneider lenses and so
rare in others? You'd think Schneider might have found a way of fixing the damn
thing in all these years.
Bob G

But he also noted that these are Schneider lenses and display the
typical Schneider problem of bubbles in the blackening between lens
elements and barrels.

I've often wondered, why is this problem so common in Schneider lenses and so
rare in others? You'd think Schneider might have found a way of fixing the damn
thing in all these years.
Bob G

"Bob G" wrote in message
...
But he also noted that these are Schneider lenses and
display the
typical Schneider problem of bubbles in the blackening
between lens
elements and barrels.

I've often wondered, why is this problem so common in
Schneider lenses and so
rare in others? You'd think Schneider might have found a
way of fixing the damn
thing in all these years.
Bob G

Its caused by flaking of the anti-reflection paint on the
edges of the lenses. This is applied to lenses where there
might be total internal reflection from an edge, not all
elements require it. The paint is also used to seal the
edges of cemented lenses although this is not the issue it
was when Canada Balsam was used for cementing.
I don't know why Schneider had this problem. It seems to
affect lenses made from the mid 1950's to about the mid
1960's. Its the sort of thing that takes so long to show up
that it may not be known to be a problem for a very long
time.
The effect is of bubbles at the very edge of the lens.
Careful examiniation will show that these are not actual
bubbles in the lens. This is a problem only if enough light
is scattered from the edge to increase lens flare,
generally, it is of no significance.
The problem can be fixed by disassembling the lens,
cleaning off the old paint, and repainting. The best paint
currently available for this is sold in the USA as Krylon
Ultra-Flat Black. It comes in spray cans so a small amount
must be sprayed into a small container for use. Apply it
with a small brush or a cotton swab. It must be thoroughly
dry before the lens is reassembled. At one time a product
was made by 3M (I think) called Velvet especially for lens
anti-reflection paint but its been off the market for years.
This stuff had the advantage of not outgassing. Outgassing
can be a problem when paint is used in sealed lens cells
because it can cause a haze to form on the lens surfaces. In
fact, such a haze is quite common and is visible when a
flashlight is shown through the lens. Even a slight haze
will destroy image conrast. Its easy to clean off but the
lens must be disassembled to do so, a PITA.


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

Richard or anyone else: Can you describe what this bubble effect
looks like. i.e., what one should look for if this were to be
visible or be a problem? The lens I'm looking at shows some fine
hair-like particles in the elements when examining a wide open
lens, but I have no idea what these bubbles look like.

Conversely, if there is no apparent bubble effect it appears
the opinon is the lenses are of otherwsie high quality for
pictorial use?

Richard Knoppow wrote:

"Bob G" wrote in message
But he also noted that these are Schneider lenses and
display the typical Schneider problem of bubbles in the
blackening between lens elements and barrels.

Its caused by flaking of the anti-reflection paint on the
edges of the lenses. This is applied to lenses where there
might be total internal reflection from an edge, not all
elements require it. The paint is also used to seal the
edges of cemented lenses although this is not the issue it
was when Canada Balsam was used for cementing.
I don't know why Schneider had this problem. It seems to
affect lenses made from the mid 1950's to about the mid
1960's. Its the sort of thing that takes so long to show up
that it may not be known to be a problem for a very long
time.
The effect is of bubbles at the very edge of the lens.
Careful examiniation will show that these are not actual
bubbles in the lens. This is a problem only if enough light
is scattered from the edge to increase lens flare,
generally, it is of no significance.

The problem can be fixed by disassembling the lens,
cleaning off the old paint, and repainting. The best paint
currently available for this is sold in the USA as Krylon
Ultra-Flat Black. It comes in spray cans so a small amount
must be sprayed into a small container for use. Apply it
with a small brush or a cotton swab. It must be thoroughly
dry before the lens is reassembled. At one time a product
was made by 3M (I think) called Velvet especially for lens
anti-reflection paint but its been off the market for years.
This stuff had the advantage of not outgassing. Outgassing
can be a problem when paint is used in sealed lens cells
because it can cause a haze to form on the lens surfaces. In
fact, such a haze is quite common and is visible when a
flashlight is shown through the lens. Even a slight haze
will destroy image conrast. Its easy to clean off but the
lens must be disassembled to do so, a PITA.

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

BTW, pictures of the lens are at

http://members.aol.com/nospam777/caltar/

Tom Phillips wrote in message ...
BTW, pictures of the lens are at

http://members.aol.com/nospam777/caltar/

I'm guessing that this is a fairly old lens; by the 8 1/4 inch marking
& the 1/400 sec shutter speed. Newer lenses have 1/500 & focal length
not mentioned in inches. If I'm correct, what I really would like to
know is about when each of these conventions were dropped?