New Post, New Year, Another Redo

A few days ago I asked, "What do amateur astronomers do when the weather is lousy?" Today I ask, "What do amateur astronomers do when the weather is lousy, they have a cold, and they can't sleep?" Well, the answer is the same: they reprocess old images! So, I'm ringing in 2015 with a reprocess of images of the Horsehead and Flame Nebulae taken exactly four years ago today.

Flame Nebula (lower left) and Horsehead Nebula; ST80 on Vixen SP; Canon EOS Rebel XS (1000D); 12x180

Happy New Year!

Reprocessed Images

What do amateur astronomers do when the weather is lousy and they can't get out with their scopes? Well, sometimes they reprocess old data. I have learned a lot about image processing over the few years that I've been in this hobby. Sometimes it is fun to see if I can do a better job using my new skills and tools. Some of these were very challenging as I did not have all of the components necessary for producing clean images (darks, flats, and bias frames).

These are some of the images that I selected as candidates for a slide show that a friend of mine is working on for the Sam Houston State University Planetarium.

Messier 8, the Lagoon Nebula, in the constellation Sagittarius.

Messier 8, the Lagoon Nebula, on the right. Messier 20, the Trifid nebula, in the upper-left. Both nebulae are in Sagittarius. This is a composite of two images taken with my Orion ShortTube 80.

Messier 35, in the upper-left half of the image, and NGC 2158 in the lower-right. Both clusters are in Gemini.

Messier 38, in the right half of the image, and NGC 1907 on the left, in Auriga.

Messier 45, the Pleiades, located in Taurus. This is only a portion of the cluster.

Messier 83, the Southern Pinwheel Galaxy, in the constellation Hydra. It is the southernmost galaxy in the Messier catalog.

Leo Triplet. Also called the M66 group. Messier 65 is on the lower left, Messier 66 is on the middle left. NGC 3628 is located on the right. It is sometimes called the "Hamburger Galaxy."

Messier 37, in the constellation Auriga.

Sword of Orion - Quick Reprocess

Here is a quick reprocess of an older image of the Sword of Orion taken with the Canon EOS Rebel XS on the Takahashi Epsilon 200.  I hope to reimage this object sometime this winter.

Eastern Veil Revisited

I was telling Clayton, my astronomy pal over at Clayton's Wanderlust for Stardust, about the difficulties that I was having in processing my recent image of the Eastern Veil Nebula. He asked if he could try working with them in PixInsight and Photoshop. The results are amazing!

The colors of the nebula and the stars are more vivid, and the detail is sharper. These images were produced with the same set of data in my previous post!

Wide-angle of the Eastern Veil

Closeup of the nebula (NGC 6992/6995)

Closeup of NGC 6995, showing detail

This has convinced me that there is yet more that I can extract from my modest equipment. I'm looking forward to learning some new image processing techniques!

Messier 16

I imaged Messier 16 back in July 2010, but was never satisfied with the results. It was one of my early attempts at imaging with the astrograph and the Canon EOS Rebel XS (1000D).

I've learned a lot about image processing since then and have gained better tools. So, occasionally I like to go back and rework older images to see if I can make them better. I'm satisfied enough with this image to post it, but I would like to go back and reshoot it one day when I get a chance.

Messier 16, also known as the Eagle Nebula, is perhaps most famous for the Hubble Space Telescope image of the Pillars of Creation. The pillars are visible in this image near the center, although they certainly don't look as spectacular here as in the Hubble image!

Messier 16, the Eagle Nebula; Epsilon-200 on NJP mount; 19x120 at ISO-800

California or Bust, Again

I've been wanting to retry the California Nebula (NGC 1499) since my last attempt. The opportunity presented itself the other night. The sky was beautiful! But, about a half hour into imaging, clouds starting rolling in and spoiled the party. Maybe I can try again another night. In the meantime, here it is:

California Nebula (NGC 1499); ST80 on Vixen SP; 8x180

Double Cluster Redo

I've been going back through my image archives and reprocessing some of the older images to see if I can improve them. Here is a reprocessed version of the image of the Double Cluster that I shot back in September 2009:

Double Cluster (NGC 884 and NGC 869); Epsilon-200; 9x180

Another Coathanger Redo

This is a reprocessed version of the Coathanger Cluster that I posted back in September 2010. I reduced the size a bit to hide some of the image noise.

Coathanger Cluster; Epsilon-200; 13x180

North America Nebula Redo

This isn't exactly a redo of my original North America Nebula. I had been intending to try to remove the effects of chromatic aberration in the stars for some time, but found it a somewhat difficult task. Most of my attempts left unnatural looking holes in the nebula, so I settled on desaturating the purple fringes and colorizing them to more closely match the color of the nebula. This is fine for the stars that are surrounded by the nebula, but those that are surrounded by darker parts of the image now have red halos instead of purple ones. Oh, well. One of these days I might win the lottery and get a nice little apochromatic refractor.

NGC 7000, North America Nebula; ST80 on  Vixen GP; 9x180

Reprocessed Images and Something New

The recent lousy weather (for astronomy) has kept me indoors for some time now, and when that happens, I sometimes dig into the archives to see what I can reprocess.

Messier 27, the Dumbbell Nebula, was the first thing I imaged with the Epsilon-200. For some reason, I recorded all of the subs in JPEG format instead of CR2 (RAW). Regardless, I was very happy with the original image at the time. I've learned a few tricks for reducing noise, though, so I thought I'd take another stab at it:

Messier 27, the Dumbbell Nebula

For comparison, see my previous post of Messier 27.

I've never been very happy with my image of Messier 17, the Swan Nebula. Like my M27, I only collected JPEG images. The images were very noisy, which made it difficult to bring out the fainter details of the nebula without swamping the rest of the image in colored streaks. A program like Neat Image can be your friend in those circumstances.  Here is a redo of M17:

Messier 17, the Swan Nebula

And, finally, here is a "new" image of Messier 8, the Lagoon Nebula, that I imaged some time ago. I think this is the first time that I've posted it in a public forum:

Messier 8, the Lagoon Nebula; Epsilon-200 on NJP; 17x120

Messier 24, the Sagittarius Star Cloud - Redo

The recent cloudy weather has driven me to go back into my archives and re-evaluate my older images. Here is a redo of Messier 24, the Sagittarius Star Cloud.

Messier 24, the Sagittarius Star Cloud; E-200; 20x120

This version of the image has been cropped to highlight the more interesting areas. The image file is rather large (just over 2 MB), so be warned if you try to view the full-size version.

I plan on re-imaging this object when I get the chance. I'm pretty sure that I can bring out more stars from the cloud, and more detail on the dark nebulae.

Incidentally, the background image that I am currently using for the blog is a low-res version of the image above.

Messier 1, the Crab Nebula

The image below is a reprocessed version of the Crab Nebula that is posted on my web site.

I took five images of the Crab Nebula one night over a year ago, just to see what it would look like. My intention was to go back and do a proper imaging sequence when I had time. That time never came, and I have probably missed my opportunity to image it this year. As a consolation, I went back to the original five images and reprocessed them using the techniques that I have learned since creating the original.

Messier 1 (Crab Nebula), Epsilon-200 on NJP, 5x180

The Crab Nebula is probably the best known supernova remnant in the sky. Chinese astronomers noted the appearance of a "guest star" on July 4, 1054. The star was four times brighter than Venus, and visible in daylight for 23 days. It was visible to the naked eye at night for 653 days. A number of Native American groups also recorded the event in pictographs.

The debris cloud was discovered in 1731 by John Bevis. Charles Messier found it in 1758 (not realizing that it had been previously discovered), and mistook it for Halley's comet. He soon realized his mistake, and this prompted him to compile his famous catalog of fuzzy objects that are not comets--the Messier Catalog. Messier 1 gained is common name, Crab Nebula, based on a drawing made by Lord Rosse in 1844.

The true nature of the "guest star" was not revealed until the early 20th century, when astronomers compared the results of observations gathered over several years and found that the nebula was expanding. Calculations based partly on the rate of expansion revealed that the event that created the nova was the "guest star" observed by the Chinese in 1054.

Cocoon Nebula - Redo

I went back and reprocessed the Cocoon Nebula image from a few days ago. It looks a little better to me now. I'm not 100% satisfied with it, though. One thing I like about this version is that the colors of the surrounding stars are more pronounced.

IC 5146 (Cocoon Nebula) and Barnard 168