In this paper we present an approved leakage remedy process for older models of Carl Zeiss Jena photo-micrographic apparatuses. They include three models of light-tight boxes suitable for photo-micrographic apparatuses with telescopic focusing prism (model No. 1), with fixed focusing prism (model No. 2) and a special photo-micrographic apparatus for the microscope Zeiss Fluoval 2 with firmly mounted photo-eyepiece in trinocular body tube and focusing dioptric adjustable eyepiece (model No. 3). Examples of light-tight boxes used for taking pictures of micro-organism are also presented.