[APML]: Optics for Solar Eclipse

["LATTANZI, Max" <m.lattanzi@unesco.org>]

Hi everybody,

I am going to Venezuela for the solar eclipse and I am still uncertain
on the optical configuration to use. I did not decide yet on the exact
focal length to frame the sun and the solar corona.

I shall take with me a Mak 150/1800 for general astronomical use but I
do not think I'll use it for the eclipse (I might try to adapt a
telecomp...)

I am thinking to use either a Pentacon 500/5.6 (a lens, not a mirror),
or a Vixen 400/5 (aka Orion ShortTube refractor) with either a 1.6x or a
2x teleconverter. So I shall obtain either 800mm and 1000mm with the
Pentacon or 650mm and 800mm with the Vixen.

The Pentacon 500/5.6 is by far the sturdier solution even though (and
also because) it weighs several times more than the Vixen (total weight
with a Nikon F4 is 5 Kg).

Any comments or suggestions? E.g., will the heavier Pentacon on a sturdy
tripod absorb shutter or wind vibrations better than the lighter Vixen
for long exposures (I do not intend to below 1/4 sec. though).

Will I get better results with a 60/700 or a 60/900 refractor (which I
do not succeed in finding with 1.25" focuser)? A 90/1000 refractor?

Any recommendations?
Thank you for your help!

Max