Rick E Davis wrote:
Another feature that can be seen in photos, particularly for destroyers, is that ships exposed to sea and sun with a faded paint job in the Pacific during or shortly after high speed operation, will exhibit a "darker" area above the waterline where the hull has gotten wet. I remember an argument many years ago when someone swore this effect showed a "new" camo scheme on a 1943 FLETCHER that was painted in Ms 21.
I have already taken that into account.
I recognized that from Art School, when we dealt with painting "wet effects."
I plan to include a strip of darker color on my models when I put them onto their gaming bases, which will be a small wake (running at roughly cruising speed of 14 - 20 kts), and then have a small band of water-darkened hull at the waterline.
But I am still waiting on when my old employer will have a machine open up so that I can have him mill the 500 - 1,000 bases I plan to make (to sell some of them). They will be 1" to 2.5" wide, and 5" to 13" long (depending upon the ship), with a wave and wake surface that tapers off to flat at the edges.
I'm thinking about using the wave and wake patterns to make some display boards for specific models as well (with the cutout for a specific ship - such as Trumpeter's New Orleans-class, or Blue Ridge Models' Cleveland-class, or Dragon's Benson/Gleaves-class, etc.).
But for the time being.... I need to get the Ms 11/21 and Ms 12/22 Blues sorted out, so that I can have just a tiny variation in color, and a few ships that look "fresher" than others.
That is something that I wish that I could take into account:
How old the paint I am looking at in photographs is.
Because blue paints, especially during the early 20th Century, tended to fade
HORRIBLY and rather quickly in bright sunlight. They were mostly made with a Lazurite or Cobalt pigments.
Lazurite, which was the most common color for
Ultramarine, which itself was the basis for Navy Blue (5-S/5-N) has a photo-optically active Polysulfide in it that is primarily responsible for the Blue coloration.
As sunlight hits it, the sulfur catches the ≈440 - 490nm wavelength photons which break the sulfide bonds, causing the color to de-saturate (become more "grey"), and to yellow slightly (which would cause the color to catch a slightly greenish tint, which I see in some of the photos ("Seeing" isn't the right word. It is noticeable to the software I use to do color analysis, and shows up as a hue-shift toward the green by about 5% - so I "See" the number that shows a Munsell shift toward a Green Hue). The photo of the USS Pennsylvania in the drydock shows a similar greenish shift when compared to the 5-N in photos I have from a video of a BB launching that is in fresh 5-N (which I stupidly forgot to label the screen captures of the ship, or to grab a photo of the ship itself, and now I can't find the video).
Likewise, Prussian Blue (Cyanotic Blue) is one of the pigments found in some formulations of Navy Blue. Prussian Blue is an Iron Cyanide blue (Fe7(CN)18) - or, more properly Fe4[Fe(CN)6]3.
Sunlight also affects it by knocking lose the Cyanide ion (CN-), which again causes a loss of saturation, and a hue-shift toward the red (Iron oxide, because with the loss of the Cyanide Ion, an Oxygen ion will oxidize the Iron which was previously connected to the Cyanide, creating a reddish hue shift.
Almost ALL pigments prior to the 1950s where photo/optically active, and exposure to the sun caused them to change
much more than modern synthetic pigments, which are formulated to be able to either resist or repair from photonics damage to chemical bonds.
So, even though I cannot track down exactly what the formulation for "Navy Blue" (5-S/5-N) is (because I have found that there are a
LOT of colors that go by the name "Navy Blue," and most of them do not correspond to the Munsell Values I have for 5-N and 20-B.
Anyway, enough of me blathering about color spaces, chemistry and blue...
MB