Very early stack here, only 20 minutes, and this is a fairly faint nebula. But the real news is that the stack is made of 10 two-minute exposures; a serious victory in my year-long battle with cheap equipment.
I had expected that when and if I could start shooting longer subs, everything would be a piece of cake, but after shooting just a few items, it's not so clear now. My traditional method of stacking hundreds of short exposures may not be they way you'd want to do it with good equipment and a dark sky, but it does allow me to vastly improve the results with cheap stuff and loads of light pollution. And since the key to making it work is having scores, if not hundreds of individual exposures, the longer subs actually can be a disadvantage when shooting relatively bright objects. In particular, stacking huge numbers of subs allows the removal of more of the pollution. This shot is very grainy and noisy, but that just takes more exposure time to fix. What appears to be a blown-out background or a gradient problem in the upper left is actually caused by more nebulosity. Like I said, this shot is from an early stage in the process.
I keep a nice thermometer and hygrometer with me when I'm shooting. When this was done, it had fallen to 36 degrees, which is normally good for telescoping. But the humidity was 97%, which stinks. that is why the bright star-Alnitak, or Zeta Orionis-is so overblown and large. Still, makes for a pretty star.
In the next few days (while it's raining and cloudy, of course) I will be replacing even more of the mount, so in a week or so I could be back with more pictures. And with the return of Orion, I can start re-shooting things I did when I was just starting out, and will finally have some comparisons.
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