Well, yesterday and today I tried my "new" rig. For a couple years now I have used my trusty Sony A77ii with my Minolta 400/4.5 plus 2X TC - that is what I took the previous shot with and all my shots till yesterday.
Now, I am trying out something different. I bought a Kenko Pro 300 3X TC.
Seeing is TERRIBLE for the moon right now with it so low in the sky, but I am so itchy to shoot I have tried anyway. My results tell me that when I get good high clear moon, I am gonna be happy! I almost certainly will resolve more detail.
This with my A77ii + 300/2.8 + 3X TC + 1.4X TC. 1260mm!
It works great.... can hardly wait for a clear moon to shoot!!
From just after dusk 11/11/18
Waxing Cresent 19% at just 17 degrees in the sky
Stack of 320 frames.