Thanks Colin. If I am not mistaken, Birna has a 1200mm f/11. But this was about the fun of it, testing my equipment.
I do not think I will go all in with equipment I do not even have at hand. As you see, I am already outresolved by Nasos, and that's just fine.
Thanks to you too, Nasos. Putting more pixels on the moon give more details, as you certainly have shown here. Pretty hefty setup you have there, and you use it to good results.
And of course, you are right that the TC-E 1.4x and 1.7x can not be combined.