1. A method of generating a substantially optimally exposed image of a cytological specimen, comprising: acquiring a first image of the specimen at a first brightness level; acquiring a second image of the specimen at a second brightness level higher than the first brightness level; combining the respective sections of the first and second images to form a substantially optimally exposed image of the cytological specimen; selecting sections of the first image which correspond to non-nuclei components of the cytological specimen acquired at the first brightness level; and selecting sections of the second image corresponding to nuclei components of the cytological specimen acquired at the second brightness level.