[mura_gadi (Steve)]

Hello,

On one of your comments I noticed you said you could be setup and using the scope within a few minutes.

If the scope is stored at outside temperatures, like in a garage, you'd be fine. If you're taking the scope from inside to out, it will take time for a closed scope with 6" of glass to equalise to the ambient temperature.

Leave it outside under an eve or similar, wait till the temperature has dropped less than 2degrees in one hour.

Then try the optics, look at near zenith objects, that will reduce the amount of atmospheric distortion the optics have to deal with.


Steve
The dob with the open tube will cool a lot quicker, fan or no fan. The central obstruction of 37% is a big issue as mentioned, you have a 4" lens after that which is getting smallish.