UPDATE:-
Ok for what its worth... first night was very windy, so set up most sturdy tripod with weights.
Exposed three shots... Since they where single shots, have only developed the two longest ones.. of over 2 hours each, at f5.6...
Ha... both negatives clear as a whistle.. no image, ... yes, I took the dark slide out... (in fact put it under the water bottle to keep it from being blown away)
Doesn't make sense, two hours +.. heard the shutter click open, when I pressed on the cable release, and it locked the shutter open, and yes, heard it close when I released it later.
The first of the three negatives, which I did not develop, was exposed only for 14min, as suddenly behind me, hear a helicopter coming. Someone east of the Superstitions, must have needed help.. for you could see it near the horizon, way out there, with its lights flashing. So since it was early, 9:00pm+ went to bed and got up an hour later and started the second shot of the three.

Whats interesting, I'm not disappointed.
I'm going to try again, on another camping trip, into northern New Mexico, later this month. ;-)