116. Working Aperture

Working Aperture. The maximum relative working aperture of this lens is f. 22 (U. S. 30.25). It has all the regular corrections of the anastigmat lens, except for chromatic aberration, but this is eliminated after the image is focused, by the use of the smaller diaphragm opening.

117. The demonstration shown in Illustration No. 12 clearly shows the immense covering power of the Hypergon lens. The upper print in this illustration was made with a Goerz Celor No. 3 lens (8 1/4 inches focal-length), the exposure being l-25th second; while the lower one was made

Goerz Hypergon Lens Demonstration

Illustration No. 12

Goerz Hypergon Lens Demonstration

See Paragraph 117

Goerz Hypergon Lens

Illustration No. 13

Goerz Hypergon Lens

See Paragraph 112 with a Goerz Double Anastigmat Hypergon lens (No. 000-2% inches focal-length), requiring 4 seconds exposure. The camera in both cases was in identically the same position.

118. It will be observed that there is absolutely no distortion in the wide-angle view, each and every line being perfectly accurate. Some persons may contend that there is distortion of perspective, or rather an unnatural perspective shown, but it must be borne in mind that the field of the lens being so great this is unavoidable. On the other hand, if, when looking at the wide-angle view, the eyes are held at a distance from the print equal to the focal-length of the lens, this apparently exaggerated perspective is entirely done away with and the actual normal perspective seen.

119. Streets And Interiors

Streets And Interiors. The most practical application of this wide-angle lens, to the commercial photographer at least, is in photographing very high buildings located along narrow streets, and general interior views. Illustrations Nos. 14 and 15, which show respectively Park Row building and a building on Broadway, N. Y., further demonstrate the advantages and possibilities of the Hypergon Wide-Angle lens.

120. The Camera

The Camera. The Hypergon lens is most useful in cases of 11 x 14 and larger sizes, owing to its extremely short focal length. When used with smaller plates a special camera will have to be constructed, as the ready built cameras will either not permit of the lens being brought close enough to the plate, or else the various exterior portions, base of camera, etc., will intrude into the picture. Where 11 x 14 and 14 x 17 plates are used, a square bellows view camera or professional camera may be employed, providing the lens can be placed sufficiently close to the plate. In other words, the distance required between the center of the lens and the ground-glass, or sensitive plate, for the No. 0 lens, is 3 3/4 inches, and for the No. 1, 6 inches. Although a special camera is procurable through the Goerz people, anyone handy with tools can, in a few minutes, and with little expense, construct a camera box that will answer the purpose as well as the most expensive instrument.