Ross Resolux 11cm/ f4 enlarging lens image by John-Henry Collinson(Image rights)

Part of the serial number sequence of lenses made by Ross. Note that the source warns that 'anomalies' exist, and suggests that some lenses, either made by Ross from designs of other companies (such as Zeiss and Goerz), or lenses made for Ross by subcontractors, may have their own serial numbers unrelated to these.^[1]

Serial nº	Year
100	1840
3,000	1850
6,500	1860
12,500	1870
20,000	1875
44,430	1880
47,31x	1885-1890
50,000	1890-1895
81,96x	1911
86,000	1918
95,000	1921
100,000	1924
105,000	1925
110,000	1927
115,000	1930
120,000	1931
125,000	1933
140,000	1939
200,000	1947
213,000	1946-7
250,000	1960

On Goerz Serial numbers and dates Goerz Amer. Serial #'s from Eddie Bolsetzian (former Goerz Tech.) Lens # 35 1902-1903 170 1903-1905 267 1906-1908 230 1908-1909 334 1911-1914 300 1914-1918 709 1927-1937 7 730 1937-1945 799 1945-1948. On Goerz Serial numbers and dates. (former Goerz Tech.) Lens # 35 1902-1903 170 1903-1905 267 1906-1908 230 1908-1909 334 1911 -1914. Date of CP Goerz Double Anastigmatic (Dagor) Lens. Introduction II. In 1942 the Goerz lenses. “Estimated numbers of serial production of binoculars of Optische Anstalt C.P.GOERZ - Berlin Serial. The collapsible pier is marked with Serial number 23414. The focuser is marked with serial number 22168. Goerz was founded in 1886 by Carl Paul Goerz. Originally, it made geometrical drawing instruments for schools. In 1889 Goerz began making optical lens under the name of Lynkeioskop C/2. Lens making became his primary business.

Notes

1. ↑ From: Wilkinson, M, and Glanfield, C. 2001. A Lens Collector's Vade Mecum, CD-rom Version 3F. Edited by A. N. Wright. Cornwall, UK: David Matthews Associates. Chapter 11, Pages 87-88.

Links

• A selection of serial numbers for Ross cameras and lenses at Early Photography

C.P. Goerz

Berlin

Germany

Model VIIb, 75 mm

Lens Type:

Telephoto attachment. Variable separation.

For 3 - 8x magnification. Rack and pinion adjustment.

Serial Number:

186905 .

This was made in two versions for either hand or bellows cameras. The tube and elements could be purchased separately. Advertisements in the 1905 BJA list the VIIb as taking a primary lens with a different flange diameter to the example shown here. The 3' negative lens is also not listed as for use with the VIIb tube. A 3' negative suited a prime lens of 6', 7' or 8 ¼' focal length covering a 4' x 5' plate at low magnification and 12' x 16' at high magnification.

Carl Zeiss

Jena

Germany

45 mm

Lens Type:

Telephoto attachment. Fixed separation.

Helical focusing scaled to 6'. For quarter-plate.

Serial Number:

55260 .

The Zeiss Tele Objective consists of negative attachments, positive lenses and tubes which can be combined in various ways. The positive lens can be either a conventional prime lens such as a Tessar or Protar, or a specialist group called the Tele-Positve. Some tubes had iris diaphragms and shutters fitted. This example is a Tele-Negative attachment in a tube with removable focusing mount. The likely positive lens would have been a Tele-Positive of 135 mm focal length.

Voigtländer & Sohn

Braunschweig

Germany

97 mm

Lens Type:

Goerz Lens Serial Numbers

Telephoto attachment. Fixed separation.

For 15 cm primary lens. 2.5x Magnification. For 10 x 15 cm.

Serial Number:

103244 .

With:

Box.

This is a conventional telephoto attachment consisting of a negative lens for mounting behind a normal objective. The attachment is for use with hand cameras such as the Voigtländer Alpin. It fits inside the bellows and screws to the rear of the lens panel. It was made in two sizes for quarter-plate (12 or 13.5 cm objectives) and 5 ½' x 3 ½' (15 cm objectives).

Goerz Lens Serial Numbers 222