When I first started taking S.E.M. photos, we did it using 4x5 black & white film. You didn't know if you had a good image until you went to the darkroom, developed the film, and made a contact sheet.
These days we can acquire extremely fine images in real-time digital format. You can see the image as its being photographed...and after I invented and built my first color S.E.M., the images are now in color!!! O.K. its synthesized color but its still very cool!
Here are various articles and photo galleries made possible by these advances in electron microscopy...