The question gets asked from time-to-time, "What color to paint Federation ships?"
You will get as many answers as you find mini painters.
Some folks, including Tony Thomas, use a basic titanium white from the bottle, which certainly looks clean and nice.
Some folks go with a "battleship gray" light gray scheme. Personally, I steer away from that as it would be too similar to the slightly-blue light gray I use for Klingons.
Personally, for my Federation ships I hew a bit more to the "as seen on tv" look and use a very-slightly green light gray.
There is new research and data from the restoration of the original filming model that slightly altered this color, but not enough that I'm worried about it at our scale.
Regardless of anyone else's opinion, the right color to use is the one that looks right to you. If that color is turquoise nail polish, so be it - get the minis on the gameboard and blow some stuff up with it.
