Method and arrangement for changing the spectral composition and/or intensity of illumination light and/or specimen light in an adjustable manner, wherein a spatial separation into radiation components of different polarization is carried out with a first polarizing device, a spectral, spatial splitting of at least one radiation component is carried out with first dispersion device, the polarization state of at least one part of the spectrally spatially split radiation component is changed, and a spatial separation and/or combination of radiation components of different polarization are/is carried out by a second polarizing device, wherein a spatial combination of radiation components which are changed and not changed with respect to their polarization state is advantageously carried out by a second dispersion device.