I have seen/glimpsed it many many times visually with/without filters in scopes from 6" newt's up from dark skies and the suburbs (we all still use 1.25" EP's - cant use 2" in these dobs due to design features ) - but not in any great detail usually of course, but just the dark bite out of the brighter nebula as was mentioned before, mostly. I had the use of a mates 13" f5 dob (I had access as his - 'field tester' - for his homemade scopes
), and his filter collection, including a HB? and OIII for a few years. That was my favourite DSO scope I have evr used at dark sites, but I also had my best look at jupiter ever thru that scope!. One commonly known method we like to do a lot with a dob for these dim objects, is to hold the end of the dob (while avoiding the heat from your hand in the view!) delicately with tips of fingers, and just jiggle the end around a little ever so slightly (like panning for gold) - enough to get your dark vision activated - ie dim moving objects night vision feature from our primitive night hunting days - ugg. same as averted vision really. But practice is what makes it easy of course - if you look at something enough it gets very easy - if you already know what your looking for or at. you must train your eyes if you are new at it, I am finding you just get better at it really until your eyes go i guess. I am blessed still for now (on knees praying) with reasonably good eyesight-
Cheers
Fringey
PS welcome Asimov
another west coaster eh!
