Yes, thats the problem with paint, it seems to be impossible to get a really matt black one. I've sprayed the inside of the tube but still think I'm getting reflections off the walls. This one is the same ID as the objective so will look at 3 or 4 baffles spaced accordingly and see how that goes. The tube is PVC so fairly light and the baffles will add very little to the overall weight if I make them from plastic material (lids of ice cream containers comes to mind
)
Thinking I might try and mix up some sort of flocking using the small tin of flat black I have here and a texturising material. We have a walnut tree in the garden, must be dozens of old nuts lying under it.
Cheers
Bill