In my previous post's comments, Velu mentioned that his ship's binoculars could use something to make them easier to find during the night when the bridge is kept dark(I enjoy reading his Bills of lading blog).
So I dug up my old 7x35 binoculars, that my Granny gave me back in the mid 1980's, and put a couple of 5 lead 4 bight Turk's head knots on them, with some 3/32" glow-in-the-dark cord from CoolGlowStuff.com. I left enough room on the end so the lens caps will still fit.
I'm sure the ship's binoculars are larger and of a higher power, so a bigger Turk's head knot would most likely fit.
At least a couple of knot books have different knot work shown on some of the older styled ship's spyglasses/telescopes. Even the book I followed for these Turk's head knots, Stuart Grainger's 'Creative Ropecraft' has one on the cover and inside.
Several types of spyglasses can be found thru Google, both long models and the smaller extendable telescoping ones - both old and new. I may get one of the inexpensive ones off ebay eventually to try some knot work on...