There is a metal detector just inside the entrance to the embarkation processing area, next to the X-ray machine for your carry on bags and prior to your getting to the check-in plaza.
Normally you are also be required to pass through a metal detector (with nearby X-ray unit) as you re-enter the ship on return from a shore excursion. You didn't indicate your destination, but if you are on the Elation to Ensenada, they also have a metal detector and X-ray machine that you normally have to pass through (and then again when you board the ship).
There are no metal detectors at the exit of the cruise.
~ MattInSoCal
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