Photomicrographer James E. Hayden, RBP has been a consistent winner of the Small World competition for many years. Featured below is a photomicrograph of a canine bone specimen taken with darkfield illumination.

Canine Endochondrial Bone Original Magnification: 39x Specimen: Decalcified bone section stained with Acid Fast Technique: Darkfield Illumination

The colors of stained sections as seen in darkfield are created by a combination of factors. Ultimately, changes in the refractive index of the various structures affect the wavelength as they pass through the specimen, creating a different color spectrum from the brightfield view. Depending on the original color of the section, the composition and density of the structure in question, and the thickness of the section, the new colors that are created provide information about the content. Acid Fast stain creates a striking red and blue combination in bone structures as seen in brightfield, but not much color difference in the bone sub-structure. When viewed in darkfield, however, the calcified regions are remarkably different from the uncalcified areas. However, in this section, I must admit to mainly seeing an unfortunate reindeer with a bullseye on its side. This photomicrograph was awarded an Honorable Mention in the 1997 Small World competition.