showtime said:you will only see NNNN if its a print from film. digital prints do not display those fields.
just recently i made some digital prints from digital files myself. the status string codes are all behind the prints. for some of them i can see the operator did density adjustments, for some my colour is off and he did the appropriate CMY adjustments. this was on a Frontier machine.
you can also check out the Frontier link a few posts earlier.
i think perhaps there are some labs where by the digital prints have no status strings on the back of the prints, even if it was a Frontier machine, as i experienced with one lab i tried.
azure mentioned something related to this a while back:
http://forum.clubsnap.org/showpost.php?p=587142&postcount=3