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I am driven to this by my recent 10 nights at a site over 100km north of Broken Hill. There was no artificial light on the full 360 deg of horizon. A couple of people were on site with just a handful of weak white lights, none in direct view. I had several hours of dark adaption. Any cloud that came over - on a couple of nights - was pure black to my sight.
But, as dark as it was, it seemed "bright" to me - I could fairly easily make my way around the site - and I was not getting the contrast I had hoped for in my views of galaxies. I also could not pick out the "Dark Doodad" in Musca in my binoculars as clearly as I have done at Snake Valley. When I asked the property manager, he felt it was darker in the winter months - so I am planning to visit again mid year.
I felt I could see a faint shadow being cast by my hand held to the sky (no Moon nor Jupiter, nor Venus). But, for the first time ever, I noted that, when I rubbed my hand across the plastic table top, I could see sheets of static discharge at the edge of my hand - quite a sight! But perhaps that was the ultra dry air conditions (rel humidity below 20%, temps in the high 20s overnight!)
So, I need an objective measure of "how dark".
(BTW, a fuller report on my "bush trip" is to come.)
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