i thought modern proofs were all cameo. this proof ike has zero on the reverse, like a business strike would. its not just a very light cameo, there is none on any devices, while the obverse has it on all. cant find any pics of any without cameo either.
Not from the 70's, no. Lots of the proofs have no cameo at all. It depends on the die state - the younger the die, the more cameo contrast. But I think there are other factors involved that someone like Doug and others could explain. Newer proofs use all kinds of Star Trek technology to get the cameos, so all the coins get them.
I don't know about Ikes, but with Kennedys it's recent - within the last 10 years practically every proof is DCAM.
In 1973 the mint began making an effort to ensure that all or most of the Proofs were cameo. Over the next 2 or 3 years a few would slip through that did not have the cameo, but not many. They struck so many of the bicentennials, they struck them in '75 & '76, that you can occasionally find one with little cameo or like yours, with it on 1 side only. But as a general rule most of them are cameo. By '77, '78, it's almost unheard of to find Proofs with no cameo.