A question – but first some background by way of introduction...

I've gone the typical route of a lifelong "journal interest" in
astronomy that started (and ended in practical terms) with a dept
store refractor. A recent bonus (some 30 years later) made it possible
to indulge a long-term lust for a Meade GOTO scope. So about 4 weeks
ago I bought a used 10" F/10 and have since spent nearly as much again
on a micro focuser, dew control, eyepieces, filters (on back order)
and books. CCD will have to be funded with the next bonus :-)

I've followed a (disturbingly) typical learning curve on this scope
too (only 5 sessions so far):

1. Digest MAPUG, absorb loads of theory and opinion, buy an LX200
2. Setup, look – ETX90 (other new scope - another story) is better!
3. Decide cool-down time must be critical (didn't believe). Next time…
4. Setup, cool down, look – improvement, but still not good. So…
5. decide collimation is MUST do too, not just "should do". Next time…
6. Setup, cool down, (deep breath) collimate, look – ecstatic!!!!!
7. discover looking is a skill which improves with practice too!
8. Next time, clarity and seeing better – now understand the effects
9. Friday night – best views yet including (possibly) difficult
objects

Although I "knew" all these things from reading, it was just theory
and I got problems from lack of practical experience. Which leads me
to my question as that's related to lack of experience too and I hope
you seasoned observers can answer it for me. I have read much about
the joy of "dark skies" and intend to travel to find some. But what I
saw in my last session makes me wonder if I already have them over my
house (5 miles S of Buckingham in the UK)! I have no prior experience
to compare against – so can someone confirm if the following couple of
observations sound like they're from a great site (or not)?

26/7/03 @ 0200BST. Using 10" F/10 LX200 (non-UHTC) + 12mm Nagler. The
air was not stable enough for more mag than this (211X)). The Milky
Way was prominent to the naked eye; almost horizon to horizon. The
dark lanes were clear and the nebulous clumps in Cygnus looked
semi-solid. No moon and clear sky, but faint haze and light pollution
below about 35 deg to the South. Andromeda visible to the naked eye.

With the scope, I got acres of black between both components of the
double-double. I also saw 3 diffraction rings around the stars (in
focus) during a moment of particularly stable air. Is that a sign of
good skies as well as good collimation (the rings were a bit broken
due to turbulence, but there was clearly 3 concentric "layers" there)?

M27 – wasn't a dumbbell! It was vaguely rectangular with faint
semi-circular extensions to each side (as in the astrophoto in
Burnhams – but I didn't think you could "see" images like that).
Central star was a faint blue spark in direct vision, but vivid blue
with averted vision. Like the central star of M57, I expected this to
be too faint to see. Mag 13.9 isn't it?

The question is, can I improve this (very pleasing) performance by
travelling elsewhere or should I save time and petrol? At 77 metres I
know getting higher will improve seeing (less air), and I don't
discount the social aspects of star parties etc. But in general terms,
am I wasting time looking for darker skies? If I will only achieve
marginal improvement over what I get at home, then I would consider it
a pointless exercise.

What reference objects do you use (and how) to empirically compare
clarity and darkness of skies between one place and another?

Cheers
Beats