Has anybody heard of a "Rival" LF lens? Also Wollensak Series IIIa question

Hi, everybody,

I found and purchased a Rival Doppel-Anastigmat, 240mm f6.8 today, in a Betax
#3 shutter....it appears to be uncoated.
I did a Google search, which turned up nothing. Searching under 240mm f 6.8
Doppel Anastigmat turned up lenses by Meyer-Gorlitz and by Goerz, but alas, no
"Rival"
Have any of you heard of, or had any experience with this lens?
Any help would be appreciated...

I also picked up a Wollensak 4x5 Series IIIa 3 1/2" f 12.5 lens in an Alphax
shutter.
A Google search turned up only an 8x10 version of the lens...
Viewing through it is INCREDIBLY dim...I expected this, it being a 12.5, but
the unusual thing is that the aperture scale goes from 12.5 down to 45,
however, the 12.5 setting is not wide open...the aperture blades are only about
halfway open.
Is this normal, to correct for lens aberrations, or is my aperture scale way
out of whack?
Does anybody have one of these? Again, any information would be helpful...

Thanks!

Doug Allen

There's a brand of dog food called "Rival." Hopefully it isn't related to
your lens. : - )

"DuganFoto" wrote in message
...
Hi, everybody,

I found and purchased a Rival Doppel-Anastigmat, 240mm f6.8 today, in a
Betax
#3 shutter....it appears to be uncoated.
I did a Google search, which turned up nothing. Searching under 240mm f
6.8
Doppel Anastigmat turned up lenses by Meyer-Gorlitz and by Goerz, but
alas, no
"Rival"
Have any of you heard of, or had any experience with this lens?
Any help would be appreciated...

I also picked up a Wollensak 4x5 Series IIIa 3 1/2" f 12.5 lens in an
Alphax
shutter.
A Google search turned up only an 8x10 version of the lens...
Viewing through it is INCREDIBLY dim...I expected this, it being a 12.5,
but
the unusual thing is that the aperture scale goes from 12.5 down to 45,
however, the 12.5 setting is not wide open...the aperture blades are only
about
halfway open.
Is this normal, to correct for lens aberrations, or is my aperture scale
way
out of whack?
Does anybody have one of these? Again, any information would be helpful...

Thanks!

Doug Allen

"DuganFoto" wrote in message
...
Hi, everybody,

I found and purchased a Rival Doppel-Anastigmat, 240mm
f6.8 today, in a Betax
#3 shutter....it appears to be uncoated.
I did a Google search, which turned up nothing. Searching
under 240mm f 6.8
Doppel Anastigmat turned up lenses by Meyer-Gorlitz and by
Goerz, but alas, no
"Rival"
Have any of you heard of, or had any experience with this
lens?
Any help would be appreciated...

I also picked up a Wollensak 4x5 Series IIIa 3 1/2" f 12.5
lens in an Alphax
shutter.
A Google search turned up only an 8x10 version of the
lens...
Viewing through it is INCREDIBLY dim...I expected this, it
being a 12.5, but
the unusual thing is that the aperture scale goes from
12.5 down to 45,
however, the 12.5 setting is not wide open...the aperture
blades are only about
halfway open.
Is this normal, to correct for lens aberrations, or is my
aperture scale way
out of whack?
Does anybody have one of these? Again, any information
would be helpful...

Thanks!

Doug Allen

I can't help with the "Rival" lens.
Check the aperture of the Wollensak lens by measuring the
entrance pupil. This sounds technical but is actually very
easy. You need a card with a small hole in it and a
flashlight or other small light source. You can do this in
your view camera.
First, focus the lens exactly at infinity. To do this
place a small mirror over the front of the lens. Put the
card with the hole in back of the lens. Adjust the distance
until the spot of light refected back throug the lens is in
sharpest focus. The lens is now focused exactly at infinity
for the card. Set the spot of light so that it is near the
source, of course, if its exactlly at the source you can't
see it.
Now that you have the lens focused for infinity place a
sheet of paper over the front (remove the mirror) and note
the circle of light projected onto it through the lens. This
is the image of the iris as seen from the front. Measure its
diameter. This is the _effective_ diameter of the stop.
Divide this by the focal length of the lens. If its not 12.5
something is wrong. I suspect the iris doesn't open any
further because the elements of the lens may be a little
oversize to prevent vignetting.


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

Doug,

Sorry I can't help with the Rival question (although I have an OMFA
dopppel-anastigmat which I've never heard of before). But, I have a friend who
has a wide-angle Wollensak lens with a similar iris arrangement. He tells me the
lens is very soft and flare prone wide open and doesn't sharpen up until the
marked f/stop is set. I would suspect the wide-open setting would be OK for
framing but that focus shift would be significant as the lens was stopped down to
f/12.5 for exposure. I also have a similar lens in a longer focal length & Betax
shutter (never used) somewhere so I'm sure your aperture is not out-of-whack but
intentionally manufactured this way.

Joe

(Change the vOwEl in my email address to reply.)


DuganFoto wrote:

Hi, everybody,

I found and purchased a Rival Doppel-Anastigmat, 240mm f6.8 today, in a Betax
#3 shutter....it appears to be uncoated.
I did a Google search, which turned up nothing. Searching under 240mm f 6.8
Doppel Anastigmat turned up lenses by Meyer-Gorlitz and by Goerz, but alas, no
"Rival"
Have any of you heard of, or had any experience with this lens?
Any help would be appreciated...

I also picked up a Wollensak 4x5 Series IIIa 3 1/2" f 12.5 lens in an Alphax
shutter.
A Google search turned up only an 8x10 version of the lens...
Viewing through it is INCREDIBLY dim...I expected this, it being a 12.5, but
the unusual thing is that the aperture scale goes from 12.5 down to 45,
however, the 12.5 setting is not wide open...the aperture blades are only about
halfway open.
Is this normal, to correct for lens aberrations, or is my aperture scale way
out of whack?
Does anybody have one of these? Again, any information would be helpful...

Thanks!

Doug Allen

"DuganFoto" wrote in message
...
Hi, everybody,

I found and purchased a Rival Doppel-Anastigmat, 240mm
f6.8 today, in a Betax
#3 shutter....it appears to be uncoated.
I did a Google search, which turned up nothing. Searching
under 240mm f 6.8
Doppel Anastigmat turned up lenses by Meyer-Gorlitz and by
Goerz, but alas, no
"Rival"
Have any of you heard of, or had any experience with this
lens?
Any help would be appreciated...

I also picked up a Wollensak 4x5 Series IIIa 3 1/2" f 12.5
lens in an Alphax
shutter.
A Google search turned up only an 8x10 version of the
lens...
Viewing through it is INCREDIBLY dim...I expected this, it
being a 12.5, but
the unusual thing is that the aperture scale goes from
12.5 down to 45,
however, the 12.5 setting is not wide open...the aperture
blades are only about
halfway open.
Is this normal, to correct for lens aberrations, or is my
aperture scale way
out of whack?
Does anybody have one of these? Again, any information
would be helpful...

Thanks!

Doug Allen

The Wollensak lens is a copy of the medium wide angle
Protar. I just checked my B&L Protar and its the same, the
diaphragm does not open all the way. So, this is normal for
this type of lens.
My previous anwer was made from another location so I
couldn't check the actual lens then.


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