View Single Post
Old 12th March 2013, 02:02 PM
rich's Avatar
rich rich is offline
Senior Member
Join Date: Nov 2008
Location: Shebbear, N Devon
Posts: 1,644

Colour temperature does have something to do with it.

Our wind-free test tunnel at Shebbear is made from blue plastic barrels spigoted end to end. The light on any target suspended in the tunnel is therefore mainly blue; the pigmented plastic filters out the longer wavelengths. Now, the tube's maximum length is 42 yards, but no matter how I try, I cannot make any of my scopes tell me the card is 42 yards away, they all tell me it's only 40 yards. A tape measure soon proves them all wrong.
Reply With Quote