"Larry Stedman" wrote in message
...
Personally, I'd avoid a metal tube dob (Hardin, Orion), especially if
one is observing from colder climes. (Don't let that cheek or nose
touch the tube! Watch out for your hand's heat plumes!)

There are some issues here for sure, however, if the temperature is low
enough that hand heat is a serious problem (takes more than a few seconds to
dissipate after grabbing the open end ring), one will likely have gloves on
anyway. As for cheeks and noses, I've never had occasion in two years to put
either against the OTA. Even so, when it's _that_ cold, I'm either not out
there, or I have something covering my facial skin as well.

Frankly, I find that the metal tube is a non-issue. In fact, I prefer it
because it reveals air moisture long before the innards are at risk, making
an excellent indicator that it's time to start taking special measures to
prevent dewing up.

A question for the group: Does sonotube dissipate heat faster than rolled
aluminum?

-Stephen Paul