In a developer station for a printer or copier, a rotating developer roller is provided having a mixture of toner particles and ferromagnetic carrier particles accumulated on a surface of the developer roller as a layer, and a transfer zone at which the toner particles are transferred away from the developer roller. A smoothing device is provided with a smoothing element arranged before the transfer zone, the smoothing element being charged with a mechanical tension in a rest state of the developer roller and designed such that it exerts a force on and over an entire width of the layer formed by the mixture of the toner particles and the carrier particles present on the developer roller and smoothes the layer before the transfer of the toner particles. Within the developer roller at least one magnet is provided. The smoothing element comprises a magnetizable material attracted toward said at least one magnet to create said mechanical tension.