Abstract: A filter press comprises a plurality of membrane filter plates each comprising a base plate and an elastic membrane on at least one side of the base plate. The base plate has a circumferential raised plane edge portion surrounding a recess with a step-form recessed circumferential surface between the raised edge portion and the recess and a groove in the recessed circumferential surface and the raised edge portion. The membrane has a reinforced edge poriton of angular cross section with a first web lying on said recessed circumferential surface of the base plate and having a bevelled edge engaging the shoulder between the recessed circumferential surface and the raised edge portion and a second web received in the groove to provide a seal between the membrane and the base plate. The outer surface of the first web is recessed below the plane of the raised edge portion of the base plate.

Abstract: In a color printing method, a color photosensitive material is exposed in the photographing step to object illuminating light, which is recorded thereon as an optical density by photographic treatments. In the printing step, the optical density is detected to determine blue, green and red exposures, which cause the object illuminating light to be reproduced on a color positive photosensitive material so as to have neutral gray or to be colored to a standard color. An object image on the color photosensitive material is printed on the color positive photosensitive material with the most suitable color reproduction with the same three-color component exposures as those determined in printing the object illuminating light.