"Steinheil München f=725mm Quarz" Lens ... any info?

[Dr Klaus Schmitt]

Group,

I found a lens (actually several of them with slightly different focal length) which is marked "Steinheil München f=725mm Quarz" and it indeed seems to to made of Quartz (Quarz is same in German).

It looks quite similar to this one I found years ago:
http://www.macrolenses.de/bilder/Steinheil,%20Munich%20IMG_0289k_wp_b.jpg

Any idea what this could have been used for? I read in a book about Steinheil that they made Quartz lenses from natural Quartz found in the Alpes and later Brazil.

[Struan Gray]

I have seen older quartz lenses made to focus light from infinity onto the entrance slit of a spectroscope. Old visible light models usually have an air-spaced achromat (they have similar design principles to telescope objecives) but the quartz ones I saw were singlets.

[Arne Croell]

One of Steinheil's core businesses was the production of spectrographs, for many,many years. I would speculate these lenses came from some of those instruments because of their transmission in the UV. More information can be found in this book:
http://www.lindemanns.de/4DCGI/1045341453/TitelAnzeige/354683
I have it, but its back in Germany and I am in the US for 4 more weeks, so I can't check on it now.

[Dr Klaus Schmitt]

I have that book also Arne, but unfortunately these lenses are not mentioned.

Struan, I would have assumed that also, but these seem to consist of two individual lenses.

Thanks, Klaus

[Per Madsen]

Impresive "Jugend Still" letters on the lens.

Do anybody have a Steinheil numbers list with production dates ?