The equatorial tracking platforms do NOT produce field rotation. An alt-az
drive that is driven in both axes will cause field rotation but the
equatorial platforms don't.
I don't know how well the set-up will work for photography but at least one
of the eq platforms has an available dec motor and accepts ST-4 autoguider
input. See:
http://www.johnsonian.com
I just bought one of these. I didn't get the dec motor and I'm not planning
on doing astrophotography
-Leonard
----- Original Message -----
From: "Tony Hurtado" <tony-hurtado@No-Spam>
To: "TAC" <sf-bay-tac@No-Spam>
Sent: Monday, July 14, 2003 5:40 PM
Subject: [TAC] Big Dobs on EQ mounts
(I saw something like 80 minutes for one model, but that's not really a big
limitation, is it? Also, there is a field rotation issue.)