Best Method To Differentiate Between A Proof And A DCAM

Why do cameos appear black in the field?

To my knowledge Deep Cameo(DCAM) and Cameo(Cam) are both descriptions of the appearance of coins. Proof refers to the process in which the coin was made and has nothing to do with the condition. I believe they treat modern proof coins with chemicals to achieve the frosted look, but in older proof coins(I'm not sure of when 1960's?) the frosting was not intentional, making DCAM examples much more valuable. The completely frosted devices with a strong contrast to the field is considered DCAM, Coins where the contrast is not as strong or the frosting is weak are CAM. Cameo literally is the amount of contrast and can describe coins that are not proofs if rarely. I borrowed this definition of proof from Wikipedia.

It has to do with the lighting and angle of incidence equals angle of reflection.

Say you are taking a picture of a proof that is laying flat on a table and you have the camera directly above it shooting straight down. And your light is coming in from 3:00 at a 40 degree angle above the horizontal. The light that hits the mirror finish fields will reflect off toward 9:00 once again at a 40 degree angle above the horizontal. (Angle of incidence equals angle of reflection) But the camera is at 90 degrees so VERY LITTLE of the light that hits the fields is reflected up into the camera. (a little reaches the camera because the field isn't perfectly smooth so a little gets scattered upward) The light that hits the rough surfaces of the frosted devices though is scattered in all different directions and lot more of it gets scattered up into the lens. The large difference in the amount of light results in the large "black fields and white devices" contrast you see. As you raise the lighting angle toward the 90 degree point more and more of the light hitting the fields gets reflected into the camera and the black and white contrast disappears,