With the huge amount of cell images produced in bio-imaging, automatic methods for segmentation are needed in order to evaluate the content of the images with respect to types of cells and their sizes. Traditional PDE-based methods using level-sets can perform automatic segmentation, but do not perform well on images with clustered cells containing sub-structures. Furthermore, DIC images contain a phase gradient, which should be removed first. We present a method that removes this gradient, finds the cell centres and derives the relevant individual cells.