What is Deep Cameo or Ultra Cameo?
Ultra or deep Cameo is a designation that applies only to proof coins. It is the measure of the contrast between the frosted devices (raised portions of the design) and the mirrored fields (all the flat areas of the coin). On a Modern coin, you should expect for it to be Ultra or Deep Cameo. When you get to older proofs, it is often times an exception, not a rule, that a coin be Ultra Cameo, or even Cameo. Cameo is a designation for a coin that has a certain amount of contrast, but not enough to be called Ultra Cameo.
The cameo effect seen on older proof coins comes from early die strikes and eventually dissipated as the die was used. Some proof coins even have partial cameo effects on the highest points of the devices. Though, this is not considered cameo even it may appear to be cameo from certain angles.
Unfortunately, there is no official rule about measuring if a coin is Ultra Cameo, Cameo, or not at all. This is something that can only be gained through the experience of looking at and studying many coins. As with all of numismatics, look at as many coins as you can. It is the best way to learn about them.
Note: The deep and ultra cameo references are trademarks of the grading services PCGS and NGC, hence the difference in terms. While there is no real difference between the extreme cameo effect, it is merely trademark terminology that has forced NGC to used Ultra. Similar to the First Strike designation that PCGS has trademarked and now forced NGC to use Early Release instead.
