Optical system production method includes (a) providing (S2) a distribution function (g) for a zero-crossing temperature (ZCTR) of a coefficient of thermal expansion (αR) of the raw block as a function of a location (p) of the raw block, (b) ascertaining (S3), an aberration (Fi) of the optical system, for the provided distribution function and each of a plurality of positions (Pi) of a cutout region (D) of the raw block that differ from one another with respect a radial position (ri) and/or a height position (hi) of the raw block, and (c) ascertaining (S4) at least one selection position (Pa) of the cutout region (D) as the position (Pi) for which the ascertained aberration (Fi) is less than a predetermined threshold value (SW).