"M97, The Owl Nebula in Ursa Major"
Prior to the bad weather, my agenda for the first quarter of
the year was to image Orion and its surrounds one more time (I am still not
satisfied with my Flame and Horsehead Nebula shots). My plan was to also image
The Eskimo Nebula in Gemini at full focal length in the 102GT, without the
focal reducer. I find I get very good images of small objects when using such a
setup. I managed the last one easily from my backyard one clear night with a
nebula filter in tow. Since the window for Orion had passed, my next objective
was to go for Ursa Major and re-image some of its principal objects, namely M81
(Bode’s Galaxy), M82 (Starburst Galaxy), M101 (Pinwheel Galaxy), M51, and M91
(The Owl Nebula). All of these objects are bright and rather easy, with the
exception of M101 due to its face on nature, spreading its light across a
rather large portion of the starry sky. I have imaged this galaxy in the past,
but with my 102GT equipped with a 0.5x focal reducer. This time I was going to
attempt to shoot it with my RFT, the 400mm focal length 70mm Celestron Travelscope.
"M82 in Ursa Major"
Setup was as usual. I started imaging with the Travelscope
70 at full focal length (can’t use the focal reducer anyway even if I wanted to
with this setup) on the NexStar GT mount coupled with the Meade DSI II OSC.
With this, I can usually go up to 42 seconds exposures without trailing. I
intended to push the envelope tonight, and with everything working in synchrony
(which happens once in the blue moon!), I managed to even get the exposures up
to 1 minute without trailing. I targeted 10 to 15 exposures at 42sec to 1
minute each for the objects. The main bug bear with alt-az GOTO mounts without
a wedge is the field rotation. And this problem is exacerbated the closer you
image to the pole star, something which I was doing tonight. As such, I had my work cut out for me post
processing. Also the light pollution from my dark sky site is worse towards the
north. This also showed up in my images as muddy background, despite the multi-image
stacking. Still, overall I was pleased with my results. The Owl clearly showed
its true nature (and colors), as well as its two eyes, something that was
missing from my “grainy” first attempt back at Solstice Canyon, Malibu when I
first started imaging with my rig.
"M51, The Whirlpool Galaxy in Ursa Major"
M101 looked heaps better in the wide field shot, even with
the muddy background, with its spiral arms and condensations indicating star
forming regions standing out against the background. M51 is a great object to
image and never disappoints, its spiral arms popping out from the background
and reaching out towards its neighboring NGC galaxy. M81, as always, was a
pretty meh object to image as it’s tightly wound spiral arms are notoriously
difficult to image unless you get a very deep image of this galaxy. After
completing my imaging run, I swapped my imaging scope out for my visual scope,
the 102GT and perused some of the summer wonders rising from the east. Hit M57,
as well as some of the now setting galaxies in Virgo and Coma. Observed till the
batteries died at close to 2am!
"M101, The Pinwheel Galaxy in Ursa Major"
With the rainy weather now behind us, and the balmy summer
skies beckoning, I might actually take a break from imaging to enjoy the
wonders of our milky way through my larger scopes. But who knows, the
astrophotography bug might strike yet again and I may target some of the
smaller summer planetaries. Till the next time.
