View Full Version : How old is my Ross lens?

Tony Kearney
14-Nov-2018, 02:59
Hi, I recently bought a Ross Zeiss Anastigmat f8 433mm (17") lens with a detenting lever that works an iris via a slot from f8 to f64 (not waterhouse stops). My problem is that it has an engraved serial number of 2xxx (which would place its origin in the 1840s) but I'm pretty sure it should be a 5 digit serial number 2xxxx which would locate it in the late 1870s. Haven't been able to find much info on this lens (rarity, value, usefulness) so am asking if anyone can help me out. Tony

14-Nov-2018, 03:54
Take a look at my last post here: http://www.largeformatphotography.info/forum/showthread.php?148522-Another-age-question-R-amp-J-Beck-lens which would seem to suggest that it is later rather than earlier. I'm finding the same problem - whilst there is information out there its rather patchy with regard to early British makers. You may want to wade through the archive at the RPS (http://rps.org/about/history/journal-archive) which is searchable although pinning down stuff like makers and dates can be a slow business.

Steven Tribe
14-Nov-2018, 05:53
Dear Tony!

The 1890's were a period of panic for some well-known lens makers , like Ross and Voigtlander! Taylor & Hobson, CP Goerz and Zeiss all had patented anastigmatics in production. Goerz, and especialy Zeiss, made their optical designs available - at a price! - to lots of people. Ross had arrangements with both Goerz and Zeiss, whilst Voigtlander had somewhat shorter term arrangements with Zeiss (Protars) and T,T & H (Cooke triplet designs).

All licensees, except Ross, used continuations of their normal serial numbers. Ross started a whole new serial number series for the Goerz and Zeiss patent loans. It is not known whether there were two series that covered G & Z individually or a single series that included both!

Voigtlander made the same lens as yours - or at least planned to! It was in his catalogue (1894) but records show it was never actually made in this biggest size. Ross can't have made a lot this size.
It is a series IIa, F.8 focal length 433, diameter of 61mm for the front lens and was given a coverage of 33x44cm.

We don't do valuations here, but remember that rarity doesn't always equate with high demand and value.

Tony Kearney
14-Nov-2018, 06:37
Thanks Steven, that explains a lot. Sorry about enquiring about value, new to this so my mistake. The measured diameter of the front element is 61mm and tested focal length is close to 433mm. Can the date of manufacture be determined by this alternate set of serial numbers? Would it be an 1890s lens?

14-Nov-2018, 07:25
There is no way an anastigmat lens was made before the 1890s. My guess for this lens would be 1895-1900. The iris alone would be a tip off.

Kent in SD

Tony Kearney
14-Nov-2018, 19:33
There is no way an anastigmat lens was made before the 1890s. My guess for this lens would be 1895-1900. The iris alone would be a tip off.

Kent in SD

Hi Kent, I also own a Dallmeyer 2A with a serial number 15xxx which according to the Dallmeyer Archive puts it's date of manufacture somewhere around the late 1860s. It has an iris so I had assumed (wrongly?) that the Ross might have been from the same era. Tony

Steven Tribe
15-Nov-2018, 01:42
The 2A would have originally been with Waterhouse slot and stops. The Dallmeyer lens would have had a "Professional" life for at least 1/2 a century and more than paid for a modern conversion to an iris aperture.

Tony Kearney
15-Nov-2018, 04:59
Thanks again Steven