The interior was already primed by Joe but I decided to take it one shade darker and fuller using Krylon® 4290 Camouflage Paint with Fusion Technology.
Masked the exterior with some tape and newspaper as I wanted the outside unpainted to keep thermal equilibrium better to ambient
Deep inside the tube
A sample of the tube's interior with flocking material against the primer. The flocking material also went against the tube's interior opposite the focuser drawtube