A measuring arrangement for measuring optical properties of a reflective optical element, in particular for microlithography, with an EUV light source (5), a detector (20) configured to detect EUV radiation reflected at the reflective optical element (10), and an imaging system (30, 40, 50, 60, 70, 80, 90), which images object points on the reflective optical element onto respective image points on the detector, wherein the imaging system is configured to reflect the EUV radiation, a first optical component (31, 41, 51, 61, 71, 81, 91), and at least one second optical component (32, 42, 52, 62, 72, 82, 92). Both at the first optical component and at the second optical component, reflection angles with respect to respective surface normals that respectively occur during reflection of the EUV radiation are at least 70.

A measuring apparatus that measures an optical characteristic of a surface in accordance with a standard selected from a plurality of standards is provided. The apparatus includes an illumination device configured to illuminate the surface with light from a light source, an imaging device configured to image the light source with reflected light from the surface illuminated by the illumination device, and a processor configured to process image data having number of pixels obtained by reducing number of pixels of the imaging device by a reduction rate to obtain the optical characteristic of the surface. The processor is configured to determine the reduction rate based on the selected standard.