In the image above, it is quite obvious that there is texture to the photographic paper. This is brought out by the epi-DIC technique, but is not obvious with other techniques.
In the brightfield image, you see that the individual grains are visible, even at 10x, and that the "black" region is still quite bright. Next is BD darkfield and then Disco Lights Illumination, which was very much the same as darkfield in this case, both of which make the dark/bright boundary quite evident. Next is with crossed polarizers, but that may be harder to interpret with an absorbing medium like silver particles.
Here is a DIC view that distinctly shows the boundary between bright and dark.
Here we see the effect of the rotating input polarizer. Note that sometimes features appear as "hills", and sometimes "valleys". (9.2 MB .GIF)
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