Two old buoys

click photo to enlarge

I've always been amazed by the fact that we continue to have traffic lights that use green to signify "Go" and red to indicate "Stop". Given that up to 8% of males and 2% of females experience red/green colour blindness you'd think that we'd have taken this into account in their design, or have long ago changed the colours to ones that aren't mis-read so frequently. Colour blind drivers are known to use the position of the lights to determine what to do, and I don't often read about accidents caused by this reason, so perhaps its not the problem I imagine it to be.

I was thinking about this as I photographed two buoys on the docks at King's Lynn, Norfolk. They were very faded, but were clearly red and green. Pairs of newer and better painted buoys nearby were also red or green, but much brighter. Their juxtaposition made me wonder if sailors experienced the same potential for confusion when steering by these buoys that mark channels. However, in preparing this piece I read that in most of the world (except the Americas, the Philippines and Japan) green buoys are conical and indicate starboard, and red buoys are cylindrical and show port. So, the designers of this navigation aid contrived a system that was legible in high contrast light (silhouette) and by colour blind people. But why did they use potentially confusing red and green? Was it simply to mimic the lights that ships carry? It seems that many of our designs, like the QWERTY keyboard on which I am writing this blog entry, have a life that extends much longer than good sense would dictate, and inertia is as strong a force in our "ever changing" world as it ever was!

photograph & text (c) T. Boughen

Camera: Olympus E510
Mode: Aperture Priority
Focal Length: 20mm (40mm/35mm equiv.)
F No: f7.1
Shutter Speed: 1/125
ISO: 100
Exposure Compensation: -0.3 EV
Image Stabilisation: On