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View Full Version : Goerz Lynkeioskop serie F N 1 (150mm); serial n103360



tomaso.favale
15-Jun-2015, 08:22
Hi, may I know what the numbers (24 - 48 - 192 - 384 - 786) engraved on the rotating iris mean?
Many thanks
135522

Steven Tribe
15-Jun-2015, 08:31
This is an old European F scale (there were quite a few of these!). If you seArch for old f scales you will be able to find the right one.

The F series was well thought of and this RR/Aplanat design was made up to WW1 at least.
Fully open, it is an modern F 14. Covers 18x24cm and 105 degrees.

tomaso.favale
15-Jun-2015, 09:46
Thanks for your useful explanation and for your prompt reply

Chauncey Walden
15-Jun-2015, 11:36
Maybe the Stolze System? https://camerosity.wordpress.com/contents/f8-and-be-there-fstop-numbering-systems/

Peter Yeti
15-Jun-2015, 12:42
No, it's the "Goerz system" in the very helpful link above. 24 is equivalent to f/16 of the modern scale and each full stop is half or double the previous one: 6/12/24/48/96/192/384 = 8/11/16/22/32/45/64.

Peter

Louis Pacilla
15-Jun-2015, 12:58
Maybe the Stolze System? https://camerosity.wordpress.com/contents/f8-and-be-there-fstop-numbering-systems/


No, it's the "Goerz system" in the very helpful link above. 24 is equivalent to f/16 of the modern scale and each full stop is half or double the previous one: 6/12/24/48/96/192/384 = 8/11/16/22/32/45/64.

Peter

The "Goerz system" stops are also in the link that Chauncey provided.:)