TOH, not your imagination, the Vin. Emps do have a white film with coating over it.
The white film is more durable than the clear film IME also.
Ambassadors use a milkier film than white, but they used to be white film. I think that kind of head is available to order though.
One thing I dig about Remo is, they offer most of their head models for 6" through at least 28-30" and sometimes up to 40".
Some new models stop at 16"--but I also use an 18" drum, so that right off the bad makes that model that stops at 16 a head I wouldn't bother with even trying.
The thing I like about the Ambassador is, the sound first, but that it'll work on any size drum, and will sound great in any situation. It's a plain old, reliable head that works without much fuss.