Here is an example of how it would work, let me know if it doesn't answer your question.
There are three concealed targets around me. I activate Stealth to use Deadeye.
I call Deadeye on all three targets.
Target A uses Camouflage; Targets B and C do not use a defense. I see Targets B and C, but not Target A.
After Target A's Camouflage expires, I may not call Deadeye against him again unless I activate another use of Stealth.
OOG: Zelda Turqman