[njsteve]

To get accurate photos of indented stampings you need to light the area in question from a shallow angle, and take a ton of photos with the light moving up in angle each time. A little water can aid in providing contrast once it starts evaporating. Any indented areas tend to absorb and hold the moisture longer than the virgin, cast material thereby providing a better image.

Kind of like the sun rising from the horizon of the block's edge, up to about 45 degrees. You are trying to get a shadow to cast into the indentions. Taking a photo with the light hitting perpendicular to the surface only serves to wash out any possible stamping marks.