peter brooks
29-Sep-2021, 12:31
I've just bought a lovely Taylor, Taylor and Hobson (Cooke) Series IIIB 8½" F6 (barrel) lens. The beauty ring says Aviar (the TTH code for these F6 varieties is Aviarica) but also 'X 5' and 'COPYING' .
The Vade Mecum says of this series
Some may be engraved "Copying" and adjusted for close-up, eg 5x on a f6/8.5in lens at No511,042, which is a beautifully coated lens marked ' Series IIIB 5x Copying'.
Lens boffins:
1) How would a lens be 'adjusted for close-up'?
2) This is obviously a process lens optimised for close distance but what does the 'X 5' mean? Five times life size? Or what?
I may not fully understand your answers but I'm intrigued to know. :) I have several IIIBs and other Aviars and am aware that they are a dialyte type design.
Thanks!
Peter
The Vade Mecum says of this series
Some may be engraved "Copying" and adjusted for close-up, eg 5x on a f6/8.5in lens at No511,042, which is a beautifully coated lens marked ' Series IIIB 5x Copying'.
Lens boffins:
1) How would a lens be 'adjusted for close-up'?
2) This is obviously a process lens optimised for close distance but what does the 'X 5' mean? Five times life size? Or what?
I may not fully understand your answers but I'm intrigued to know. :) I have several IIIBs and other Aviars and am aware that they are a dialyte type design.
Thanks!
Peter