Welcome back, Rick!
The Photo Pass at the Walt Disney World Resort is only for use there, and not on Disney Cruise Line. Disney Cruise Line uses a system similar to the Photo Pass, however there are a few differences.
On the ships, your Key to the World Card will serve as your photo pass of sorts. Just like in the parks, each time your photo is taken, the photographer will scan your card to assign that photo to your stateroom. Then, you can go to
Shutters, the photography shop onboard, and view your photos, either by prints that are waiting to be seen, or on the digital screens. Guests are able to purchase individual photos or buy a cd collection with a few different choices of packages.
One big difference on the cruise ships versus in the parks is that your photos will not be available to view and purchase after you leave the ship, so be sure to buy any must-keep photos while you're onboard!
I hope that helps as you plan your trip, Rick! Whether you buy a photo package or not is up to you, but do be sure to bring your own camera as there are endless photo opportunities onboard and in the ports!
Have fun with your last minute details before you set sail!