Sorta yeah, sorta no. The screen vehicles appear much darker than the physical props were, that's for certain. It has to do with the film stock used to shoot Aliens. That, and the fact that they ran out of time to fine tune the color corrections in post production. AS a result, you have this discrepency between props and how they appeared in the movie. Its the same thing with the Pulse Rifles. Show a casual fan an M41A in true "brown bess" and they'll say its the wrong color.