The present disclosure discloses a spectrometer arrangement including an entrance-slit group including a slit wheel and a slit mask for introducing radiation into and for limiting the optical field of the spectrometer arrangement, a first dispersive element for spectrally decomposing the radiation in a main dispersion direction, and a second dispersive element for spectrally decomposing the radiation in a transverse dispersion direction that forms an angle with the main dispersion direction to yield a two-dimensional spectrum. The slit wheel is mounted rotatably about an axis of rotation and has a falcate opening having a width that changes depending on the angle. The slit mask includes an opening that is longer than a largest width of the falcate opening such that radiation radiates through the falcate opening of the slit wheel and the opening of the slit mask. The present disclosure further includes a corresponding method and an optical component group.