Modulation Transfer Functions of Photographic Emulsions

All photographic emulsions suffer, to varying degrees, from two flaws - they have a limited ability to record accurately minute details and they add noise to whatever they record. To the electron microscopist attempting to do high resolution work on biological material using low electron exposures, these flaws can be of critical importance. The choice of exposure, magnification and emulsion used will determine the amount of detail recorded and the relative influence of the added noise. These choices thus dictate the transfer of information from the image to the emulsion and limit its retrieval by optical and/or computer processing techniques. How does one make a sensible choice?