Hello.
I think I’ve found a bug in the observatory. Lenses can be allocated to higher rank slots if you use the “Shift+Right Button” hotkey while selecting a prophecy. My character has rank 6 in the Fortune Faction and I was able to place 3 lenses, which should have been impossible given that the last one is rank 9. If this is not a bug, please disregard. Sorry about the English.
Thanks.