if Astrophotography might be on the books, definitely go for a Sky watcher dob 8 or 10" with 8 being slightly more preferable as it mounts better to the NEQ6-w Mount.
The reason why i say go skywatcher over bintel/GSO is that i will focus without chopping the tube or replacing the focuser with a ultra low profile version.
A 8 or 10" will give you the views that wont dissapoint but the 12" can do it better, but when it comes to mounting the 12 for photography, your going to need a 8k mount to do it properly.
have a squiz at my website some of the photos had been taken with a 10" dobsonian on a EQ6Pro mount just so you can understand what you can do with this type of setup.
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