Hi Richard, Do you require visible light only?
In any case, i remember a neat paper describing using Hoffman modulation, as well as polarisation and phase contrast. Pure analog computing ;) What stroke me then (and now) is that the standard microscopy kit people use does not use the variety of optical tricks available (bar the wavelength doubling/halving trick some are using). Phase contrast, for instance, is such a simple add on to microscopes - a hole with a patch in the centre. Check that: J. Appl. Cryst. (2003). 36, 1295-1296 [ doi:10.1107/S0021889803013724 ] Microscope detection options for colorless protein crystals grown in lipidic cubic phases P. Nollert Cheers, Jose'
