A disguise has to suit the observer it must fool and the distance from which that observer sees the ship. In the fictional example from Master and Commander, a sailing warship masquerades as a merchant vessel to draw a heavily armed French privateer close. That deception aims to encourage an approach. Graf Spee's problem was observation by aircraft at a distance, where an altered silhouette could delay identification. The comparison explains why the intended observer matters when judging whether a disguise would work.
Chapter · 2:21-4:18
Graf Spee and Master and Commander: who must the disguise fool?
The disguise had to match the enemy observer and the range at which identification would occur.