An online database of camouflage used by 
United State Naval Warships during WWII

Measure 16
Thayer System
(Source: Ships-2 Rev. 2 June 1942)

USCG Northland wearing Measure 16 Paint Scheme

Vertical Surfaces:

Vertical surfaces from boot-topping to top of superstructure masses including masts, A pattern consisting of Thayer Blue 5-B and White 5-U.

Special Characteristics.

The special feature of this system is its changeable character.  At low level of illumination a blue paint will appear relatively lighter and a red paint will appear relatively darker than these two paints appear in daylight.  This visual change, known as the Purkinje effect, is utilized in the Thayer System.  The pure light blue which is employed has been selected because it will appear practically like white paint at low levels of illumination.  The ship will therefore appear like a white ship on moonless nights or during twilight when white or very light ships are best for reduced visibility.  During daylight hours or under bright moonlight the pattern will appear and will produce some deception in the estimation of the target angle.  A darker blue would produce more deception but can not be used because it will not appear white at night.  The purity of the color is an important factor in the Purkinje effect, and even a slight admixture of black in the paint will reduce its effectiveness at night.

Horizontal Surfaces:

Horizontal surfaces, Deck Blue, 20-B.

Wood Decks.

Wood decks except on submarines and carriers shall be darkened to the color Deck Blue.  Deck Blue paint shall be used in lieu of stain for this purpose.

Canvas Covers.

Canvas covers visible from the outside vessel are to be dyed a color corresponding to Deck Blue.


The camouflage painting need not be exact or carried into corners.  Small gear, wires, rigging, and areas permanently in shadow, as under boats, etc., need not be painted with the camouflage colors.  There is no objection to exact or careful painting which may be desired for the sake of good appearance at close range.

All bright or shiny objects, no matter how insignificant, shall be painted, covered, or removed.

Glass windows shall be covered or removed, especially during the day in sunny weather, and at night when anticipating searchlight discovery.  Insofar as conditions permit, similar precautions shall be taken on airport lenses.