We print directly to plexi or polycarb for backlits. They are 4/C White 4/C per the manufacturer day night application.
iPrint: This problem has been occurring for about 6-8 weeks. As I stated we hooked up our old rip Onyx 7.3 that used to be fine and still have this issue. Today we ripped the same file in Caldera and we still see this pin dotted bkg. on the back lit images. It just seems like the white is not dense enough as it use to be heavier. The file is set up 4/c white flood 4/c the day night application. On the old rip nothing has changed, we also have a Fuji acuity that's doing the same thing. We have tried different plexi brands to eliminate that avenue. Both machines have white bags that were made around May 2012.
As a side note we are running the 255 WHite and 256 4/C but it has not been an issue in the past. The tech is going to have us try the 256 white to see if that changes anything. Our back lits just have this sparkly looking bkg in the light box, first off I figured it was the led light box but we had an old sample print off the fuji that looks as solid as can be. We're really looking at it being ink since both machines are doing it but so far they claim nothing has changed. Very frustrating. Are we being more picky about it? I don't know but I do know it didn't use to be that way. We have just spoke with a printer in another state who is now saying they are having the same issue getting the white to print at the density it use too. Thanks for your input!