A method for determining sample container characteristics is presented. The method comprises providing first image data representing a first image of a sample container in a first scenario, wherein in the first scenario, a first illumination condition comprising a sample container background illumination is applied to the sample container; providing second image data representing a second image of the sample container in a second scenario, wherein in the second scenario, a second illumination condition different from the first is applied to the sample container; determining a mask from the first image that indicates a sub-image section of the first image comprising a sample container representation in the first image; determining sub-image data from the second image containing a sample container representation in the second image by applying the mask to the second image; and determining the sample container characteristics from an image data analysis comprising image sub-image data data analysis.