Monday, October 5, 2015

#15 - Monday, October 5, 2015 - Finally, some not-so-bad images!

What luck to get two nights in a row of mostly clear skies.  It was humid though, and it had been warm that day and was still kind of warm, so the visibility was pretty poor.  The sky was even brighter than it was on Sunday night.  (Actually, most of the sky was pretty dark on Sunday night).  This was my friend Jared’s first time looking through a telescope, and he was thoroughly impressed.  We caught Saturn just before it set, so it wasn’t very clear, but you could still see it reasonably well with the 13mm eyepiece.  We also looked at the Andromeda galaxy, a few clusters including Hercules, Butterfly and Double, and double star Mizar and Alcor in the Big Dipper, which is now mostly behind the trees to the northwest.  There were a bunch of persistent and spread-out airplane contrails, along with a few other high-altitude clouds, which made the visibility even worse, so finding a suitable object for photography was difficult.  I tried the Omega Nebula, but didn’t get many pictures before it wound up behind a cloud.  I only got four good ones (again, cable got jiggled and several were turned into JPEGs), which stacked reasonably well, but is also grainy and dim.  This one is a promising target – I have another version where I increased the luminosity, and you can see even more of it, and it’s quite pretty – but it’s close to setting, and it’s in the southwest where all the light is, so this might have to wait until next year.
M17 Swan Nebula - you can really see the swan here!
Nikon D3100 on my C8, 4x20s, ISO-3200

After having to give up on the Omega Nebula, I couldn’t find any other nebulae that were a) bright enough, b) high enough in the sky, and c) not too high in the sky.  It seemed like everything was either between 10-15° or above 70° [above the horizon].  On the other hand, if I can go out on another weekend night before it gets too cold, the North America nebula is starting to get low enough in the sky on toward midnight or 1 AM that I could try to image part of it – it’s huge!  Also, the Orion nebula is now rising at about 12:30 AM, so if I can go next weekend, I won’t be able to start imaging it until about 1:30 AM, when it’ll be closer to 20° high.  But it is very bright - +4 magnitude – so maybe like 60 or 70 images will make something good.  We’ll see.  Also, for the record, Stellarium is a fabulous app for planning!  Other things to try include the Eagle Nebula, which I haven’t tried yet because during the summer it was too high, but now that it’s lower, I took a 30-second single exposure just to see if I’ll be able to see it, and I can’t see really any gas at all.  On others like the Omega, Lagoon and Dumbbell Nebulae, the gas is apparent even in a single exposure.  So I’m not sure I can take long-enough pictures of it to be able to get anything worthwhile.  That one might have to wait until I get a focal reducer. 
After giving up on the Omega, I ended up just imaging the Double Cluster, which looks nice in the telescope, but star clusters don’t make for great photographs, at least I haven’t been able to do very well.  There is very little color information; the RGB curves are nearly delta spikes. [As it turns out, you want the RGB curves to be narrow spikes in your RAW images].  So this was 17 images (out of 57 originals) taken of the Double Cluster, or, at least, half of the cluster.  It’s pretty large, apparently.
Part of the Double Cluster, taken with my Nikon D3100 on the C8.
17x20s, ISO-3200

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