I just wrote this in response to another thread but it struck me as so important I thought a new thread was called for.
I was having a beer with my friend who skippers about 50,000 tons of bulk carrier and he made a very interesting observation. Twice they have had to sheer off hard - not easy for a boat that size - because the color of "white" LED mast head & steaming lights is almost exactly the same as a star. He explained, those lights tend to be weak and look exactly like stars from a few miles away. They are so small you do not notice them getting closer on a moonless night until you are right on top of them. This from a very experienced and careful professional seaman who also owns a lovely sail boat. He uses loads of LED's on the boat but not for his navigation lights. Next time in a dark anchorage look at the other boats mast head lights and you will see what he's talking about right away. Meggi once mistook one for Venus and was waiting for it to get a bit higher so she could practice with the sextant.
I was having a beer with my friend who skippers about 50,000 tons of bulk carrier and he made a very interesting observation. Twice they have had to sheer off hard - not easy for a boat that size - because the color of "white" LED mast head & steaming lights is almost exactly the same as a star. He explained, those lights tend to be weak and look exactly like stars from a few miles away. They are so small you do not notice them getting closer on a moonless night until you are right on top of them. This from a very experienced and careful professional seaman who also owns a lovely sail boat. He uses loads of LED's on the boat but not for his navigation lights. Next time in a dark anchorage look at the other boats mast head lights and you will see what he's talking about right away. Meggi once mistook one for Venus and was waiting for it to get a bit higher so she could practice with the sextant.