gundlach rapid rectigraphic convertible

[n_dhananjay3]

Does anyone have any information regarding this lens? Its a triple convertible (13 1/2", 20 1/2" and 28") from around the turn of the century (not the last one, the one before that). I was wondering if it was related to the Turner Reichs. More to the point, I was wondering about possible shutters I could adapt it into. Its in some gamey 'Unicum' kind of shutter right now. I guess Packards might be an option but I was hoping someone might be able to tell me keep my eyes skinned for a Betax No 4 or something. Cheers, DJ.

[dave_willison]

Check out the following link for a brief history on Gundlach and other

Rochester lens manufacturers:

 

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http://www.cif.rochester.edu/~ardavis/history/kingslake.html

 

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It looks like Reich was an optician and Turner a machinist. Ernst

Gundlach has his own history, including a stint with B&L.

 

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On the lens, I have one reference which lists a Gundlach-Manhattan

Rapid Rectigraphic Convertible with 14, 20 and 28 inch cells. The

reference indicates that all three cells combined yield a 14" focal

length and a maximum aperture of f8. The rear cell (alone) provides

20" at f16, and the front cell (alone) gives you 28" at f22. The

reference also indicates that the lens is composed of 10 elements in

two groups (is that possible with a triple convertible?). As far as

coverage, all three cells combined are listed as covering 8x10. The

rear cell covers 14x17 and the front cell 16x20.

 

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I assume the lens is uncoated and that the quality of the lens

degrades (like most convertibles) when cells are used alone to produce

increased focal lengths. I hope this information helps.

 

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...........................

[sean_yates]

"The reference also indicates that the lens is composed of 10

elements in two groups (is that possible with a triple convertible?)."

 

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Indeed it is not only possible but quite likely for a Gundlach

convertible. The front cell is one cemented group of five cells, and

the rear likewise.

[chad_jarvis1]

I own one of these. Mine is labeled "Gundlach-Manhattan Optical

Company Rochester NY Rapid Rectigraphic 8x10 Front Lens 28 In. Pat

Dec 9-1890". Contrary to what Sean stated, this one is definitely

not a 5 element per group design. That may be true for the Rapid

Rectilinear (though I recall that being fewer as well), but this one

appears to be in two element (three max) groupings. Mine is also 13

1/2 - 20 1/2 - 28 but is mounted in a Gundlach two-

cylinder "compound" style shutter. It is crap, but it has a Feb 8

1900 patent date on it and works well at T, B and 100. I've

considered having it adapted to my Copal #3, but...

[sean_yates]

Here's what Rudy has to say

 

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"In 1890 Ernst Gundlach, then living in ROchester, New York, patented

a variant of the Rapid Rectalinear in which he used three cemented

elements in each half instead of two. The numerical construction of

this lens was not disclosed, but probably its performance did not

differ significantly from that of the Rapid Rectalinear."

 

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So where the source citing 5 cells in two elements got the info from

is anyone's guess. Kingslake does have this to say though, which is

kinda neat:

 

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"If you compare the structure of the Zeiss Quadruple Protar Series

VII with the structure of the Turner-Reich lens, (the commonly

available convertible) it will be seen each consists of an old-

achromat on the outside with a new-achromat doublet close to the

stop. The difference between the two designs is that in the Zeiss

lens the old-achromat is similar to half a Rapid Rectalinear. while

in the Turner Reich lens the old-achromat resembles hald of

Gundlach's Rapid Rectagraphic objective. As the performance of the

of the Rectagraphic and the Rectalinear were basically the similar,

we may expect to find the Turner-Reich lens would be no better than

the Zeiss Series VII, which is indeed the case."

[tracy_storer1]

I believe the 10 element reference (two groups, five elements

each ) refers to the construction of the Turner-Reich, which came

after the Rapid Rectigraphic. I have a couple rectigraphic cells,

but have not gotten around to using/testing them yet. Someday...

Tracy Storer