. Electric railway journal . ts of aportable lamp with reflector, which is moved along toillumine successively all parts of the interior which isto be photographed. The photographs used in Mr. Lancasters article else-where in this issue show what can be accomplished bythis plan, and a brief description of the apparatus andmethods used to obtain these photographs is given inthe following paragraphs: The camera needs no description—almost any typewill serve—but an anastigmat lens of the cemented typewill give negatives that are more brilliant than a lensof the air-space type under tunnel conditi
. Electric railway journal . ts of aportable lamp with reflector, which is moved along toillumine successively all parts of the interior which isto be photographed. The photographs used in Mr. Lancasters article else-where in this issue show what can be accomplished bythis plan, and a brief description of the apparatus andmethods used to obtain these photographs is given inthe following paragraphs: The camera needs no description—almost any typewill serve—but an anastigmat lens of the cemented typewill give negatives that are more brilliant than a lensof the air-space type under tunnel conditions. Thereis no need for a large aperture. Most of the photo-graphs used by Mr. Lancaster were taken with thelens stopped to full. The plates must be backed ordouble coated. The lighting apparatus consists of a1000-watt, 110-volt, tungsten, concentrated filamentlamp mounted in a mirror reflector, designed in sucha way that the light from it is very evenly diffused, withno concentrated ray, but only one small dark spot in. HAND-CAR WITH PROJECTION LAMP the center of the circle of illumination. The reflectorand lamp are shown in one of the photographs. To obtain a long perspective of a tunnel the lampmust, of course, be carried down the tunnel ahead ofthe camera and pointing away from it, thus illuminat-ing every part of the tunnel successively, starting di-rectly in front of the camera and ending, say, 10(70 it, or whatever distance is required in the photo-graph. The lamp may be carried in the hand and cur-rent fed to it by a wire of the required length attachedto the tunnel lighting system, but for long perspectiveviews it is better to mount the lamp on a small pushcar connected to an electric locomotive about 250 by means of a light rope and a wire for furnish-ing the current to the lamp. The man attending the
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyorkmcgrawhillp
