The C11
was malfunctioning pretty terribly. I
put the guide scope on it, borrowed a 7 lb counterweight from Bob, and
got it all balanced, and then got started aligning. Its initial guesses were terrible, but I
aligned it anyway, and then went through polar alignment, which was waaaay
off. So I tried it again, same
result. So then I took off the guide
scope and kept trying, but it would just keep slewing past where the star was
in declination during alignment, and I could hear the motors running at higher
pitch than normal during some parts of the slew. Around 2:30 AM, I finally gave up and plugged
my camera into Bob’s C14. I
originally had the focal reducer attached as well, but I noticed that stars not
near the center were really skewed – this was because his is the EdgeHD, which
is already field-flattened, so the focal reducer (which is also a field
flattener) un-flattened it. It took a
while to find the objects because his finderscope wasn’t aligned very well, but
we eventually found the Trifid Nebula! I
took about 90 images on it, since the focal ratio is f/11 on his scope, so
objects would be dimmer. Despite the
especially small FOV, it came out quite well, especially after some Photoshop!
M20 Trifid Nebula, Nikon D3100 on a 14-inch Schmidt-Cassegrain, no focal reducer
65x30s, ISO-3200
Had to use Super Pixel + 2x Drizzle mode because of odd star shape (wasn't quite focused)
Still a
little out-of-focus, but I think I’m eventually just going to have to get an
auto-focuser because the critical focus is to tight on SCTs that it’s nearly
impossible to achieve perfectly visually.
This is 65x30s at ISO-3200. I
unfortunately had to use super-pixel and 2x drizzle in order to get them to
stack because of the un-focusedness of the stars. But stack it did. I also grabbed some images of M13, the
globular cluster, but I haven’t copied it over to my computer yet. We went to sleep in our tents at around 4:30
AM.
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