A further update to this thread now I've had the chance to do a few more observing sessions. All, unfortunately, from my light polluted London back garden (sqm 18) - I'm really looking forward to getting these to a dark site to see what they can do under much better conditions.
Anyway, last night I decided to get up at 2am to have a look at the lovely emission nebulae that is now visible at that time. It starts not being fully dark at about 3.40am in London, so there is a relatively limited time to observe these objects.
Cygnus had got to a relatively decent height and the 3 degree fov (with 55mm plossl for an effective speed of around f3) presented the North America very nicely. It was easy to do a one eye vs two eye comparison by just turning off one of the units. It still surprises me how much using two eyes improves the views and it is in a number of ways I find:
a) the view looks more natural and smooth and less "electronic".
b) the view has a bit of "depth" impression to it which I like
c) less scintillation which means that I generally run at higher gain than single eye, ie brighter
d) the fine detail of the nebulae is much cleaner and more obvious
e) faint clouds of nebulae are much easier to detect. Despite the light pollution, I could see lots of general wispy nebulae in Cygnus which I generally need a darker site for.
f) added comfort of keeping both eyes open and looking naturally at an object.
Once I'd had a good look at the North America, Pelican, Butterfly, Crescent and Veil I moved south to where the Eagle and Swan were just poking out over the neighbour's roof. These were really quite low (around 15 degrees) and never in my experience that good because the light pollution is so poor even with nv and filtering. However, last night I got some of my best London views of these objects, the swan really stood out with the circular surrounding nebulae very clear and the Eagle shape was nice and clear.
The darkness was by then beginning to disappear so I moved gradually back to Cygnus for one last look. On the way I noticed that sky safari's h-alpha view showed some brightish "blobs" to the right of Cygnus, just below Albireo. Two in particular stood out and although I'm not really into chasing faint sharpless objects I decided to try for these two. Both of them I could see pretty easily with the binoscope, certainly much easier than without. I wasn't sure what they were at the time, but today I looked them up in my Bracken Astrophotography sky atlas and it turns out they were Sh-2 86 and Sh2-92. Two new objects for me I think and ones I will come back to at a dark site.
I then recalled GeezerGazer mentioning the propeller nebula above Sadr. I'd not looked at this before but again it was clearly visible with two eyes. For some reason, I also found that averted vision worked well with two eyes to make the nebula pop out that bit more.
I had a final scan round Sadr and the North America since the detail and extent of nebulosity was just so fun to observe and then packed up around 4am for some extra sleep.
This scope is fast becoming my favourite way to do night vision observing. I also ordered another 27mm panoptic to get some more image scale (at about 26x mag) on smaller objects such as globulars and galaxies, maybe two eye will mitigate the slower speed with the 27mm. There are a number of clear nights forecast here over new moon so I hope to be able to try this soon (at a more reasonable time of the evening!)