The 1953 set above described as "DCAM" is barely frosted at all - it looks like a perfectly average specimen of the set.
As for 1977 crowns, there are two proofs: one is the CuNi from the standard year set, and isn't frosted. The other is the silver proof, sold separately in their own cases, and all have a virtually identical degree of frosting; 'CAM' I would say, but if others wish to say DCAM... [shrugs] ... won't affect the price, which has barely moved in 40 years.