refractor tubing, sizes, tube currents, etc.

Have finally decided to use aluminum tubing for the 10" doublet. Have several choices, 10" or 12" diameter tubing.

10" tubing, cheaper, lighter, and will fit an existing equatorial mounting. 10" tubing comes very close to the edge of the light path near the doublet.

12" tubing, more expensive, heavier, stronger, needing a new mount, new worries about tube currents.

Tube wall thickness available: .064" and .094"

My biggest concern here is air currents in the 10" tubing and wall thickness.

Thoughts and recommendations please?

Hi Kreig,

Sounds like a very nice lense. Is it a D&G ?

IIRC I have read on these forums about lining the inside of an aluminum tube to insulate it, and reduce tube currents.

Maybe a search on "tube currents" might get the listing.

The 12" tube should also be much stiffer than the 10" if it's going to be a long one.

I'd guess the 10" tube would require a more complex / larger counter-cell in order to get the lens out front of the tube entrance a little bit? Baffles would be easier on the 12", anything working inside it would be easier?