1. A method for inspecting a wafer, the method comprising: performing a training process for creating reference images, the training process comprising: capturing a plurality of images of a first wafer, the first wafer being of an unknown quality, each of the plurality of images of the first wafer being captured at a predetermined contrast illumination, each of the plurality of images of the first wafer comprising a plurality of pixels; determining a plurality of reference intensities for each of the plurality of pixels of each of the plurality of images of the first wafer; calculating a plurality of statistical parameters for the plurality of reference intensities of each of the plurality of pixels of each of the plurality of images of the first wafer; and selecting a plurality of reference images from the plurality of images of the first wafer based on the calculated plurality of statistical parameters, capturing an image of a second wafer, the second wafer being of an unknown quality; selecting a first reference image from the plurality of reference images; and comparing the captured image of the second wafer with the first reference image to thereby determine at least one of presence and type of defect on the second wafer.