Let's see... i'll have problems translating the exact officer or warrant officer to the equivalent in brit navy, which i know from Patrick O'Brian novels, but i read the spanish edition. <img src="http://www.piratesahoy.com/forum/style_emoticons/<#EMO_DIR#>/blush.gif" style="vertical-align:middle" emoid="

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Captain's uniforms are all the blue upper ones except the 1928 one. The 1700 one is a captain, but not really a 'uniform', in that year, there was no standard uniforms in the navy, but captains and officer used scarlet and red casacks and clothes.
The 1793 ones that are next to each other are captain 'mourning' uniforms, right one is for 'family mourning'.
The one at the bottom is a Captain out of duty.
The 1928 red uniform in blue background is a 'guardiamarina' (young officer).
You're right, the yellow one is the surgeon, but in the spanish navy it was not a warrant officer, but one of the "sea officers" ('oficiales de mar mayores').
The red ones, 'pilotos' are not captains they are also one of the 'sea officers', called also 'oficial de derrota', a graduation that accordingly with Patrick O'Brian books, also existed in brit navy, but as i have the books translated to spanish, i dont know the english word. They were the ones responsible of the navigation and course of the ship, i hope you know the brit equivalent.
I dont' think that warranted officers (boatswain, master gunner, etc...) had a standard uniform in the spanish navy, at least ive never seen one.
For Leutnant, here's a link to another part of the same site showing a 'teniente de navÃo' uniform in detail:
<a href="http://armadasiglo18.free.fr/armada18/acuarelas.htm" target="_blank">http://armadasiglo18.free.fr/armada18/acuarelas.htm</a>
There's also a naval infantry soldier pic in the bottom left in the same page.
I hope this helps <img src="http://www.piratesahoy.com/forum/style_emoticons/<#EMO_DIR#>/biggrin.gif" style="vertical-align:middle" emoid="

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