1. A method for determining operating characteristics of a photometric detector comprising a plurality of photosensitive pixels, the method comprising: illuminating an active surface of the photometric detector with electromagnetic radiation; recording a plurality of varying brightness readings for the various pixels in the plurality of photosensitive pixels on the photometric detector; calculating signal statistical dispersion values for the plurality of photosensitive pixels independently on a pixel-by-pixel basis over the plurality of varying brightness readings; calculating stable intensity values for the plurality of photosensitive pixels independently on a pixel-by-pixel basis over the plurality of varying brightness readings; and approximating a photon transfer curve based on the signal statistical dispersion values and the stable intensity values wherein the photometric detector is adapted for biological analysis.