Changing cut sheet size for Epson P9000

[TJ-421]

I've got a P9000 I'm using for color prints from a 36" roll and imposition proofs on 42" x 33" sheets. That sheet's getting harder to come by and we're looking to switch to 40" x 28", but I can't seem to find where I tell the printer that's the new size, and my proofs come out offset like it's still expecting the wider sheet. The Windows box driving it has the roll and cut sheet size set to Letter, sheet width sensing on the printer itself is enabled, and changing the sheet size in the queue settings in ORIS appears to be having no effect. Is there somewhere else I should be looking?

Much obliged,

-TJ

 

[schenkadere]

You can tell it to print on center in Oris. Granted you may know that and may have tried that. Just a thought.
I have 3 P9000's driven by Oris Color Tuner. Off topic, but not a fan of the Oris overly complicated interface.