Extragalactic background light: a measurement at 400 nm using dark cloud shadow*†– I. Low surface brightness spectrophotometry in the area of Lynds 1642

We present the method and observations for the measurement of the Extragalactic Background Light (EBL) utilizing the shadowing effect of a dark cloud. We measure the surface brightness difference between the opaque cloud core and its unobscured surroundings. In the difference the large atmospheric and Zodiacal light components are eliminated and the only remaining foreground component is the scatt...