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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 |
#2
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Has anybody heard of a "Rival" LF lens? Also Wollensak Series IIIa question
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 |
#3
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Has anybody heard of a "Rival" LF lens? Also Wollensak Series IIIa question
"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 |
#4
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Has anybody heard of a "Rival" LF lens? Also Wollensak Series IIIaquestion
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 |
#5
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Has anybody heard of a "Rival" LF lens? Also Wollensak Series IIIa question
"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 |
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