Sunday, February 19, 2017

#76 - Sunday, February 19, 2017 - The Big Leagues

Another clear night!  And it was a little darker than Friday night.  It looked like some clouds were going to roll in around 10 PM, but that didn’t happen, thankfully.  Although I did get some ground fog around midnight – however, the telescope didn’t seem to care and saw right through it.  I did have a battle royale with dew though, which killed my external battery before I plugged the dew heater in instead. 

I started out with the Rosette Nebula, a new target for me.  It’s too big to do with my 11-inch, although I might try a mosaic sometime if I can get that process down.  I could just barely make out some differences in contrast in the subframes, but HOLY COW did this come out awesome!  It came out all right from DSS, but a little Photoshop really made it pop.  Since my camera isn’t very sensitive to red, I have to massage the colors a bit to make it more realistic.  This one is probably my new favorite.
Rosette Nebula, Nikon D5300, Vixen NA140ssf, Astronomik CLS filter
Guiding: QHY5 on Celestron 102mm
23x300s, ISO-1600
[Note: This is now an award-winning image!  I won second place in the 2017 OPT/Astronomical League astrophotography contest in the Deep Sky category!]

The detail is amazing, and I even picked up some of the blue from the cluster in the center.  Oh, also, an AstroBin user commented on one of my images and mentioned a piece of freeware called Noiseware (well, there’s a paid version too, but they have a free version) that really does a wonder with noise.  I tried Photoshop’s noise filter, and it doesn’t even come close.  Unfortunately, it only saves out small jpeg files (a couple of MB), so not good enough to print.  I’ll have to see if I can either get Photoshop’s to work better, or see if the paid version does TIFFs.  
I think I will use this one for my upcoming astrophotography talk to my club, since the subs have a lot of skyglow and you can barely make out the nebula:

After 2 hours on Rosette, I switched over to the Pleiades before they set, and I did have to re-sync the mount, even though they are nearby.  Luckily, its guess was okay for the sync star, and I didn’t have to go that far.  I was planning two hours on it too, but it dropped below 20° altitude before then, and the pictures started coming out crappy.
M45 Pleiades Cluster, Nikon D5300, Vixen NA140ssf, Astronomik CLS filter
Guiding: QHY5 on Celestron 102mm
15x300s, ISO-1600

Since this one is all blue, color balance was simple, since the filter lets through blue light the most already.  I think it captures the nebulosity pretty well, although I’ve seen better.  I might re-process to make the blue a little bluer and a little less green – I’ll have to go look at some pictures to get a good idea of what shade the blue should be.
It was just about midnight, but I wanted to get one more target in, since Monday was a holiday anyway, so I flipped around to the north to do the Leo Triplet.  I got it synced to nearby Denebola, but then my guidescope started acting up.  The new darks library I took (I didn’t realize yet that I could import it from my CGE profile in PHD) for some reason added a high background, and then sometimes the whole field was just gray with no stars.  I checked focus, shined light in it to make sure it was still reading, and finally got it working again by unplugging and replugging it, and restarting my computer.  Then I also imported the old darks library.  That seemed to get it mostly going.  That and taking test images took 45 minutes.  So I did an hour and a half on the Leo Triplet, and called it a night.  Again, I left at 2:30.  The fog was quite thick on the drive home, but luckily it still didn’t take much longer.  Galaxies are very hard to white balance with a light pollution filter, and the CLS is no exception.  My attempts in Photoshop just introduced a bunch of noise. So I gave up and kept them more or less blue.  Also, they must have turned off the lights at the nearby dairy farm because I was able to do 5-minute exposures at ISO-3200 without too much background.
Leo Triplet (M65, M66, NGC 3628), Nikon D5300, Vixen NA140ssf, Astronomik CLS filter
Guiding: QHY5 on Celestron 102mm
16x300s, ISO-3200

So yeah, a great night!  I am very pleased with the Rosette Nebula!  The memorial scope is fun to image through because of its faster focal ratio and large FOV, and also how I can get everything set up in like in 20 minutes, but the large FOV also really limits what is worthwhile to image because a lot of interesting things would just have too few pixels on target, such as M51 and the dearth of other galaxies up during the wintertime.  And for those dimmer galaxies, only 5.5 inches of aperture doesn’t do much for you.  But the flat field and pinpoint stars sure are nice.  I need to look into off-axis guiding or something for my 11-inch so that I don’t get flexure issues from the mirror moving around.   Once I get that mount fixed.  I might just send it off to Clay Sherrod to deal with.

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