Showing posts with label M21. Show all posts
Showing posts with label M21. Show all posts

Sunday, September 7, 2014

Lagoon Nebula and Trifid Nebula with Canon T5i on Orion Motorized EQ-1

Lagoon Nebula and Trifid Nebula with Canon T5i
Canon T5i on Orion EQ-1M, 240 subs, 46 darks, 81 bias, ISO 800, 6 sec, f/5.6, 300mm
In spite of the waxing gibbous moon (which happened to be International Observe the Moon Night) I got a good stack for the Lagoon Nebula and Trifid Nebula. I improved on my last attempt from last summer. Previously I was restricted to 1.3 sec exposures on a fixed tripod - obviously longer exposures on my motorized mount is paying off!

This stack is a total exposure time of about 24 minutes, which is by far the longest net light exposure I've ever done.  You can clearly see the nebulosity in both nebulae. I also spent about 2 hours processing this image, and learned a new and better way to stretch curves in Photoshop rather than in Deep Sky Stacker. DSS is nice to get a rough approximation, but curves in Photoshop come out a lot smoother.

I also used my subtract Gaussian Blur technique for light pollution to remove the hot spot gradient in the middle of the image. It was a quick fix, but it did the job. I tried using a star mask without success, I guess I just don't understand how that works just yet - but the subtracted blur layer does a nice job removing gradient fuzz.

Canon T5i on Orion EQ-1M
Canon T5i on Orion EQ-1M
With a 300mm lens, my DSLR on the Orion EQ-1 was pretty easy to get a BASIC alignment. I was happy that Polaris was just barely visible over the roofline from my backyard without needing to set up on the grass. I used live-view manual focus, and then loosened the thumb screws to slew all the way around to the southern sky.

I could get 6 sec exposures without star trails, which is shorter than I got the other night on Andromeda, because the stars closer to the celestial equator appear to be moving faster than stars closer to the celestial pole.

Monday, August 5, 2013

Messier Triplet: M21 (open cluster), M20 (Trifid nebula) and M8 (Lagoon nebula)

Three Messier objects all in one frame, not too shabby! I first saw these little guys in a wider view of the Milky Way, and I've been slowly chipping away at Messier solo numbers for my collection - but these 3 are so close together they all fit in the same frame even with my 300mm lens.

lagoon nebula and trifid nebula
89 subs, 35 darks, 35 bias (1/4000s), each at ISO 1600, 300mm, f/5.6, 1.3 sec

It turned out better than I thought. I figured Orion was the only nebula I'd be able to see with my older camera and slow lens, but I was pleased to see some nebulosity come out right away. I could probably spend some more time on this, but I wanted to get it posted and get on with processing some other photos that I took on my trip to Peoria, IL. 

This was the last stack from my mini-Messier-marathon the other night, when I also got M11 (and thought I got M29 but had the wrong anchor star... ooops).