Abstract: The invention relates to a method and plant for producing cement clinker, comprising the steps of: burning raw materials to form cement clinker in a furnace, preheating the raw materials with flue gases of the furnace, and dehumidifying and cooling flue gases of the furnace by means of a condensation heat exchanger.

Abstract: A stack of individual sheets of film is enclosed by lightproof plastic packaging. An opaque sheet is disposed at the bottom of the stack, and the side of the opaque sheet confronting the packaging is provided with a bar code containing information about the film. The packaging is removed in a lighttight area of a processing unit for the film and the bar code is read. The opaque sheet prevents the radiation used to read the bar code from reaching the film. The information retrieved from the bar code is employed to control processing of the film.

Abstract: A device for producing photographic exposures of images appearing on an image screen onto a film platform carrying a plane film comprises a support holding a number of objectives and displaceable parallel to the axis extending through the central point of the image screen and the central point of the film platform. The platform carries one objective fixed to the platform of one magnifying property and four additional objectives which have such magnifying properties that each of them projects the picture field area of the screen on only one fourth of the usable film surface.