I've just completed a refractor using a Surplus Shed 90mm x 900m focal length objective lens, Celestron R&P focuser and GT mount. Anyone else have experience with lining the tube with black "speaker cabinet" carpet to control unwanted light reflections rather than flat black paint and aperture stops?

Surplus Shed optics
Started by
Moonstruck
, Apr 28 2014 03:00 AM
2 replies to this topic
#1
Posted 28 April 2014 - 03:00 AM
- Neil likes this
#2
Posted 28 April 2014 - 07:50 AM
Welcome the the forum Moonstruck,
We certainly hope that you enjoy yout time here sharing this great hobby of ours.
Normally, this is restricted to large apature newtons etc. However, there is no reason why it can't be applied to refractors so long as it doesn't cut into the light cone etc...
Anything that kills the unwanted reflections will work fine, baffles are normally used in refractors, however, I have seen these also made from foam rather than metal.
Clear Skies
Neil.
#3
Posted 29 April 2014 - 04:51 PM
Agreed. I would never allow obstruction of the light cone to occur, but this was the first time I used this type of non-woven carpet in this application. Contact adhesive adhered it to the fiberboard tube and I let it set open for a few days to prevent trapping vapors. The very flat, reflection less nature of the carpet seems to work well. A thin coat of sandable sealer on the outer tube wall followed by copper hammertone spray paint finished the job.