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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