on or by

[kay]

-Is the sentence below correct?

Contents of catalogs are printed on the continuous sheet
printing system while covers are printed in color on digital printers.

-Would it be more natural to use "by" in instead of "on"?
ex. .. are printed by the continuous sheet printing system

[Pete]

-Is the sentence below correct?

Contents of catalogs are printed on the continuous sheet
printing system while covers are printed in color on digital printers.

-Would it be more natural to use "by" in instead of "on"?
ex. .. are printed by the continuous sheet printing system

I think that here "on" sounds more natural.