Which alt/az mount would you all suggest for the 102?
I haven’t used it, but hear good things about the Stellarvue M2C for 4” class scopes. I bought a more expensive DiscMounts DM4 for a 4” class scope, based on my prior experience with the larger DM6, but the biggest scope I am using on it now is 92mm f6.7, and it’s an excellent combination, and I am confident it would work well with a 4” scope. For either of these mounts you will need to buy a tripod to go with it.
Keep in mind you might need to add an extension column to either of these mounts to allow a 4” f7 scope to point at the zenith before the focuser end of scope hits the tripod legs, and the extension column will add about 3# to the rig. I have an extension column, but don’t need it with my 92mm f6.7 scope, and you probably won’t need one with an 80mm f7 scope that’s lighter and about the same length.
I have no experience with Porta and Twilghts mounts, but many people here use and recommend them, but not everyone seems to think they are adequate for a 4” scope. They are less expensive than the other two mounts I mentioned, and I believe they come with a tripod. To be sure it would work well with a 4” scope, I would want to try one before buying one, or buy from a dealer with a generous return policy.
In my experience, it’s much easier to find the right telescope than to find the right mount and tripod for the scope unless I have prior experience with the mount and tripod with a similar size scope. Sometimes it seems to me that mounts and tripods only come in two sizes: too large and too small, so when in doubt I usually get more satisfactory results by choosing too large.
Edited by gwlee, 17 September 2021 - 11:04 PM.