Goerz HYPERGON 90 degree coverage only ?!!

[cwe001]

Today when I looked at lens price on a goerz catalogue , noticed soemthing abnormal.

http://yandr.50megs.com/gz/artar1/artar1.htm

In second page, hypergons are listed fix f/22 or f/32 with ONLY 90 degree coverage!!! That coverage is even smaller than a dagor..LOL, which renders it almost useless with fixed apeture.

The seem to me a diffrent series from previous 140 /110 degree coverage hypergon with the focu to be 127/135/ 168?

Anybody can cast any light on these poor coverage hypergon?

 

[Ole]

Seems strange to me. Maybe this was a repro series?

BTW, the originals were 135 degrees with the "propeller", 110 degrees without.

 

[Ian Grant]

The link you posted answers your own question.

These Hypergon are stated to be: A special lens for mapping, plotting and rectifying equipment, for military and industrial applications.

There's nothing there about only covering 90°, the asterix 90° relates to the Dagors in the section above.

Ian

 

[cwe001]

Each line of note corresponds to the lens listed above, as are the cases with Red Dot and Golden Dagor on the paper. So I think " Coverage 90* special sizes to order" referes to Hypergon on top of it.

 

[Ian Grant]

Look again: In the Dago section above the Hypergon there are specific markers after the film sizes, this relates to the 90° coverage of the Dagor at those film sizes. It goes on to say special sizes available to order. It appearrs the symbol is a # rather than an asterix *.

Note there are no # at all in the Hypergon section. It is very clear that the 90° coverage relates to the Dago which is exactly as expected.

Ian

 

[JG Motamedi]

Yes, it looks like these were special order items for repro or mapping work made without the propeller. As a completely symmetrical lens the Hypergon would work for reproduction since as its distortion would be very low. Sharpness and fall-off would be a secondary concern, but perhaps that is why Goerz declares the coverage as 90 degrees. Coverage and illumination are not the same thing after all.

 

[cwe001]

hmm the mark after film size in dagor section look like " at light glance.

You are a real agent~ Mr Grant.

 

[Ian Grant]

I thought that at first and was going to delete my reply, but first I had another look at the page you linked to and it is apparent the the symbol is only used after the film sizes for those particular Dagor's.

Also when Goerz use the inch symbol " further down the page in the lens cap section it is different and far clearer, the font sizes are the same.

hmm the mark after film size in dagor section look like " at light glance.

You are a real agent~ Mr Grant.