Homocentric

1902

Ross Ltd

London

England

Series V No.1. f8, 5"

Lens Type:

Anastigmat, Double Gauss type. 4 elements.

Iris diaphragm to f22. Brass mount. For quarter-plate.

Serial Number:

63682 .

Notes:

Sold by J.A. Sinclair & Co. 54 Haymarket.

Designed by G. Richmond, four series were produced: f5.6, f6.3, f8 and an f8 process lens. All but the last were intended for general use especially with hand cameras. An f6.8 Compound Homocentric was of different design. An f4.5 series with an unsymmetrical layout was introduced in 1912.

References & Notes:

BJA 1903, pp. 36, 905. BJA 1905, pp. 36, 917A. BJA 1912, pp. 40, 713. N&G 1908, p. 69. Sinclair Cat. 1910, p. 127. Kingslake, pp. 118, 122. Neblette, Principles and Practice, p. 121.

Isostigmar

1906

R & J Beck Ltd

London

England

Series IV. f6.3, 3.5"

Lens Type:

Anastigmat, Double-Gauss type. 5 elements.

Iris diaphragm to f22. Aluminium mount. For 3 ¼" x 4 ¼".

Serial Number:

117576 .

The Isostigmar was produced in the following series:

I	1906	f4.5	3 - 12"
Ia	1908	f6.5	9 ½ - 19"	Long focus
II	1906	f5.8	2 ¾ - 8 ¼"	Combinable
III	1906	f7.7	4 ¾ - 9 ½"	Combinable
IV	1906	f6.3	3 - 7"	Wide-angle, 90° angle of view
V	1908	f11	11 ¾ - 30"	Process lens
VI	1908	f5.6	9 ½ - 17"	Portrait lens with variable softness
O	1913	f3.5	2 - 8 ¼"
IIa		f5.5	4 ¾ - 8 ¼"	Combinable

The Isostigmar was also sold as the Ensign Anastigmat.

References & Notes:

BP 27180/1906. BP 14673/1908. BJA 1908, pp. 118, 590. BJA 1909, pp. 112, 729. BJA 1910, p. 654. BJA 1911, p. 108. BJA 1917, p. 64. Phot. Lenses Simple Treatise 7th ed., pp. 288, 142. Kingslake, p. 120.

Omnar

c. 1901

Rathenow Optische-Industrie Anstalt vorm. Emil Busch

Rathenow

Germany

Series III No. 3. f7.7, 7 ½"

Lens Type:

Anastigmat. 4 elements 80° angle.

Iris diaphragm to f45. Black painted mount. For 7" x 5".

With:

Lens cap.

Introduced in the early 1900s, the Omnar was produced in three series: I f4.5 in lengths of 5 ⅛ - 10"; II f5.5 in lengths 3 9/16 - 17 ¾"; III f7.7 in lengths 3 ½ - 12". When first advertised the lens was known as the Busch Anastigmat.

References & Notes:

BJA 1903, p. 919. BJA 1905, p. 441. BJA 1906, p. 438. BJA 1912, p. 381. Kingslake, p. 118. Neblette, Principles and Practice, pp. 122, 565.

Company Details:

Beck

Ross

Early Photography

Homocentric

1902

Ross Ltd

London

England

Series V No.1. f8, 5"

Lens Type:

Serial Number:

Notes:

References & Notes:

Isostigmar

1906

R & J Beck Ltd

London

England

Series IV. f6.3, 3.5"

Lens Type:

Serial Number:

References & Notes:

Omnar

c. 1901

Rathenow Optische-Industrie Anstalt vorm. Emil Busch

Rathenow

Germany

Series III No. 3. f7.7, 7 ½"

Lens Type:

With:

References & Notes:

Anastigmats

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