In the Discoverse (to stay reasonably on topic) you see the same thing. On the Shenzhou bridge they look almost air force blue - but on the Discovery, Isaacs has a more brighter cobalt. so I just picked what I could get hold of without spending a fortune on samples.
For the graphic breakdown I just did an in-between. The Shenzhou bridge does make them appear more navy than they are but the one pic of Isaacs is also not with balanced properly so they aren't quite that cobalt/indigo either. I have a feeling in certain light they could almost look black. Cool for the show, setting mood, etc, a bit less so for trying to replicate the look ;-)