Hi all!
Thanks for your replies. I'm very happy for that
@Osebor and @Wings5797: I understand what you said, but I'm not agree... well or at least I'v other (my own) reasons (I can't speak for other painters) to use that blue and not a more real navy blue. The real navy blue is nearest from the balck than the blue; and for my painting style, as you know, I use a real great contrast between lights and shadows to create the volumes and the atmosphere. So if I use a real darker base, most of people could think "ok, this is black, not blue".
As you say, I can use a blue color to get a lights, but I'll find two problems. The first one is that, due the dark base that I used, I should add just a little bit of blue to don't broke the layering and I'll never get the contrast that I ussually am looking for (but if you use a flat style or an "without too much contrast" style, you won't find this problem.... but for my style is a real problem). The other reason is that most of people are in the habit to see the black highlighted with blue, this people (most of us) will think that it's a black, not a blue.
I really apreciate your comments and I don't want to justifie myself, just to explain that it's a decission more artistic intead realistic. I could paint it more realistic and I'll read a lot of comments like "it's too flat", "you need more contrast" "that uniform is blue and not black", and similars
So I preffer to get an artistic finish. And I really understand what you said!
Again, thanks for comment!