Pete, I know that 1600 seems obvious as a DX, but I recall that P3200 has "nominal" speed (Kodak's word) of 1000 . I've always taken that to mean that P3200 has a DX of 1000.(posted 8676 days ago)Since both P3200 and Neopan 1600 are both faster than the average film, it occurred to me that the 1600 was a marketing speed like the 3200 is.
I've used only manual cameras in the past and the issue of DX was an irrelevant issue for me, but now I have a Leica Minilux which does use the DX.
Sorry if my question seemed stupid to you, and maybe it is, as odds are that Fuji uses a DX of 1600.