The invention describes a method for producing a plastics film by a film-extruding machine, wherein at least two plastics materials from at least two reservoirs are fed together to one extruder or are each fed to a respective extruder, the plastics materials are melted in the extruder or in the extruders and are conveyed as a melt strand or as melt strands into a die head, the melt Strand or the melt strands are spread out flat in the die head and is/are extruded from a die of the die head as a melt film, and the melt film and/or the film sheet formed by cooling is/are drawn off by at least one take-off roll. It should particularly be noted that measured values are recorded by means of a measuring device for at least one property of at least one plastics material and/or at least one melt strand /d/ or the melt film and/or the film sheet and/or for a machine parameter of the film-extruding machine and that a first plastics material is a plastics material with varying material properties and a second plastics material is a plastics material with substantially constant material properties, wherein the first and the second plastics materials are fed to the extruder or the extruders in relative proportions, the relative proportions being varied according to the measured values for the property.