Twangster is right! On deck 14 you will go to the port side stateroom corridor. Walk as far as you can in the direction of the bow. You will reach a door that takes you to a hidden observation deck (Image attached). There are some low lights that shine down from the railing but no overhead lights. I always go here to look at the stairs.
If you are cruising the April 21-28 itinerary, I hope to see you there. On Monday night going into Tuesday morning The Lyrid Meter Shower will peak!
Best of luck!