Carl Zeiss patent combination lens with a ring type iris diaphragm. When used as a doublet the effective aperture is F.4.5 with 7 inch f.l. When the front element is used alone the effective aperture is F.12.5 witha focal length of 11.5 inches. Ross c.1910. Carl Zeiss patent combination lens circa 1910
Orthopanactinic compound lens set. Consists of 3 front and 3 back interchangeable elements and 6 Waterhouse stops. The aperture of the lens at full opening is approx F.8. The focal length can be varied from approx. 6 inches to 14 inches by interchanging the individual lens components. McGhie and Bolton, c.1890 Orthopanactinic Combination Lens Set. circa 1890
Doublet combination lens set consists of a lens barrel and 6 interchangeable lens elements of focal lengths ranging from 14cm to 38cm. The lens barrel is slotted to one of the 12 Waterhouse stops. Darloi Opticial, c.1875. Doublet Combination Lens Set. circa 1875
Wray compound lens. Lens mount for 8 1/2x6 1/2 camera with three ? achromat lenses: 9", 12",15". Iris diaphragm calibrated for three focal lengths. Two lenses. Wray Combination Lens
