I caught a sweet shot of The Moon and the red planet, Mars last night just before the clouds rolled in. The pair were separated by around 1* or so. This pairing is often referred to as a conjunction or alignment.

This was a more interesting image to process as the two are so far apart in brightness. The image I chose was a bright one (so that Mars would be visible). As such, the moon was a way washed out. To better deal with this, I created a duplicate layer in GIMP. This allowed me to process the two separately and then re-combine them later. For the moon, I used a number of Curves to dramatically reduce the overall brightness.  This revealed details on the lunar surface. For Mars, I used the Curves function to dramatically brighten the image. Not sure if this is cheating, but I took a copy of a black section and covered over the moon on this one. Otherwise, it was going to get brighter still. Finally, I selected just Mars and did an additional Curves and Levels function on just this object. This made Mars stand out significantly. Finally, I merged the two layers to create one nicely integrated image.

Astro Photo Details:

* Designation: The Moon
* Magnitude: roughly mag -12
* Size: roughly 1/2*

* Designation: Planet Mars
* Magnitude: mag -1.22
* Size: 15″

Astro Photo Processing Details

* Canon Digital Rebel XTi
* 1 x 1/2s exposure at ISO400
* Gimp Curves

Another spectacular moonrise this evening. The November Full Moon is referred to as the Beaver’s Full Moon. Here, we see the moon rising above the ’scrub oak’ on a ridge east of Park City, Utah.  This shot was taken using the Canon Rebel XTi for a 1/30 second exposure at ISO400 shooting at prime focus through the Astro Physics Starfire Refractor. I picked this image because it had the best foreground display. I processed it in GIMP and did a Curves function on it. I pushed the low end up and the midrange down. This brought out the foreground (earthly objects) and dimmed the moon. The moon was previously a bit washed out. Pulling the midrange down a bit brought the moon under control and revealed a bunch of surface detail.

What a gorgeous moonrise today. I thought of hiking up to get a better vantage point to capture tonights moonrise. A host of conflicts would prevent that. As it turned out, it really didn’t matter. Moonrise was followed by a spectacular positioning of the (almost) full moon and the Belt of Venus. The Belt of Venus is the point in the accompanying photo where the sky changes color from blue to purple. This is Earth’s shadow being cast onto the upper atmosphere. In this photo, the Moon is sitting just above the belt.

Proper polar alignment is one of the most critical issues for deep sky astrophotographers. If your mount is not spot-on as far as alignment goes, you’re going to have a heck of a time taking the long exposures needed to snag the elusive faint fuzzies that inhabit the night sky. Sure, you can take a number of short exposures and stack them. This will only get you so far though. At some point, your signal to noise ration simply isn’t high enough to reveal the details that will allow you to separate yourself from the masses. Depending on the focal length of your telescope, a poor polar alignment might limit you to exposures in the 15-30 second range, perhaps less. Beyond this, stars will elongate and quickly begin to look like footballs, or worse, lines… not the round points of light that they should be. As your stars begin to elongate, the faintest details in your exposure will simply disappear, the faint light they emit being spread so thinly that it gets lost in the background of your image. You’ve now removed any hope of creating the spectacular image that everybody is talking about.

Polar alignment, balance, mount stability and tracking smoothness will either work for you harmoniously or work against you at every opportunity. There are things you can (and will have to) do as you progress as an astrophotographer to improve each aspect of your imaging. At some point, you’ll fix one glaring issue only to reveal the next, more subtle, layer of issues. Don’t take this as a bad thing. This is a desirable progression. Eliminating the worst defects and working to remove the lesser defects, until all that remains is a spectacular image. One that you can be proud of, and one that will make other astro-imagers jealous.

The next couple of posts will focus on what it takes to get a good polar alignment. The first will simply describe the polar alignment process in detail and walk you though it. Master this, and you’ve got alignment licked. The second, will describe how some available tools can be used to improve your alignment. Specifically, we’ll look at the Gemini GoTo System and its Polar Alignment features. Other mounts may have similar features that you can use.

I took this picture almost as an after thought. I’d gone out to image Comet Holmes as it cruised by Mirfak (α Per). While doing so, I decided to image the moon to see if the two really were the same size (the actually are). I pulled the Canon Rebel off of the scope and popped in the 31mm Nagler eyepiece with a variable polarizer to reduce the brightness somewhat. Skies were actually much steadier than I’d expected, revealing some amazing details. I decided to make use of the TeleVue 2x Barlow to capture some of the added details.

I chose this view centered on the Lunar Apennine Mountains because this is one of the most dramatic features on the lunar surface. There were also a couple of distinctive craters running right along the lunar terminator that were brought into stark contrast. The lunar terminator is the line where light meets dark on the lunar surface. It is along this line that many oft missed details are revealed to lunar observers..

This shot was the best of a number taken that night. I took a handful of quick but under exposed images thinking that I might stack them. Unfortunately, minor variations caused by seeing existed that made this seem problematic. I decided that the entire process would be much easier if I took the best single image and started working from there. The accompanying image was just what I was looking for. It was a 1/30 second exposure at ISO100. It was fairly well illuminated and required just a little boost at the low end of the spectrum using the Curves feature in GIMP. GIMP is a free image processing software package that runs on a number of operating systems. I’ve used it in the past when my laptop was running Windows. Unfortunately, the laptop came with Vista, the most horrible version of Windows ever released. I suffered for about 6 months before finally deciding to load Ubuntu Linux on the machine. Its been just a short while since doing so, but performance and stability are dramatically improved.. but I digress Anyway, GIMP also runs quite well on my Linux box, allowing me to do whatever processing I need on my images.

Astro Photo Details:

* Designation: The Moon
* Magnitude: roughly mag -8
* Size: roughly 1/2*

Astro Photo Processing Details

* Canon Digital Rebel XTi
* Astro Physics Refractor f/10
* 1 x 1/30s exposure at ISO100
* Gimp Curves

Comet 17P/Holmes burst onto the astronomy scene just three weeks ago. In that time, its captured the attention of astronomers worldwide. Brightening one million fold literally overnight, the comet has grown steadily as well. From its earliest days, Comet Holmes has proved to be far more interesting than almost anyone would have imagined.

Here are a couple of interesting pictures taken last night. Both of these were taken using my Canon Rebel XTi. The first was what I went out to capture, Comet 17P/Holmes passing by the bright star Mirfak (α Per). As you can see, the star appears within the growing expanse of the comet. Set against a background of stars in the constellation Perseus, the comet continues on its merry way.

While I was out, I figured I might as well snag a shot of the waxing gibbous moon. Since it was dominating the night sky, I figured I might as well catch a couple of shots. Views of the moon were particularly crisp last night as well. I’d heard people compare the growing size of Comet Holmes to the moon, so I figured I’d compare images. Low and behold, the comet was at least as big, if not bigger than the moon!

I processed both images separately in Gimp (linux version now and then created a new image that was exactly twice the size of the originals. I then did a select all and copy and paste for each. As you can see, the two are almost an identical size. I actually have a slightly over processed version of the comet that shows it to be a bit larger than even this image indicates. I had a problem with that image and time prevented me from re-processing and using that image.

Anyway, if you’ve not gotten out to view the comet yet, now is as good a time as any, perhaps better. As the comet is almost sitting on top of Mirfak, the brightest star in the constellation Perseus, it is even easier to find than usual. Simply head outside after dark and look to the northeast. Perseus is due east of the ‘W’ shaped constellation Cassiopia. Many people are familiar with its signature shape. Due east of Perseus is the constellation Auriga lit up by bright Capella. Once you’ve identified Perseus, Mirfak is the brightest star in the constellation (along the northern ‘edge’ of stars). You likely won’t see Comet Holmes at this point as the brightness of Mirfak tends to obscure it. As the two separate in the coming days, the comet should reappear. This is a beautiful binocular or telescope object. If you have access to optics of any size, be sure to point these towards the scene. At roughly the size of the moon, this is one large object to digest. In larger telescopes, Comet Holmes will fill your eyepieces from edge to edge. This is a sweet sight. I don’t know how long the show will last, but the constellation Perseus will be visible at night through the winter. Be sure to take as many views of the comet as you can. It will undoubtedly be changing considerably over the coming weeks and months.

Astro Photo Details:

* Designation: Comet 17P/Holmes
* Constellation: Perseus
* Magnitude: 2.5
* Size: 15′ (roughly 1/2 the diameter of the full moon!)

* Designation: The Moon
* Constellation: Perseus
* Magnitude: roughly mag -8
* Size: roughly 1/2*

Astro Photo Processing Details

* Canon Digital Rebel XTi
* Astro Physics Refractor
* 1 x 60s exposure at ISO1600 (comet)
* 1 x 1/15s exposure at ISO100 (moon)
* Gimp Levels and Curves

I got out an snagged some sweet views of Comet 17P/Holmes again this evening. I viewed through both the Astro Physics Starfire 160 (6.2″) and the ObDob, a 25″ Obsession Dobsonian Reflector. Views were sweet in both, but I have to say… at least as far as telescopes go… size does matter

The comet just about filled the 31mm Nagler eyepiece. This is my lowest power, widest field of view eyepiece. At 100x and roughly 0.8*, the comet seemed to be bigger than the estimates I’ve heard. The prominent core seems to have faded… or been hidden behind all the cometary debris encircling this comet.

This comet had already blown me away with the unexpectedly great show it’s put on. I’d not expected have a comet to look forward to for quite some time. Even when I first heard about it, I figured it’d not likely be all that great. Wrong! This comet has put on an amazing show… and it’s not not done yet. I has moved a few degrees though the constellation Perseus in less than 2 weeks.

Here’s an image I processed on Saturday night from images captured on Tuesday night (11/07). That particular night, I was hoping to image the recently detected tail of the comet. I saw that a few astrophotographers had taken much longer exposures than I had. While I was trying to portray the comet as it appeared in the eyepiece, these individuals were looking for details well beyond what could be seen visually. So, I opted for 30 minutes of exposure time via (18) x 75 second expousres. I went all the way to ISO 1600 to make sure I grabbed every possible photon. When I stacked the images, I was depressed to see that I had absolutely no tail to show for my efforts. Subsequents images seen online as well as comments seemed to indicate that the comet’s tail had disappeared almost as quickly as it appeared. Comet 17P/Holmes had once again proved to be no ordinary comet.

Astro Photo Details:

* Designation: Comet 17P/Holmes
* Constellation: Perseus
* Magnitude: 2.5
* Size: 15′ (roughly 1/2 the diameter of the full moon!)

Astro Photo Processing Details

* Canon Digital Rebel XTi
* Astro Physics Refractor
* 18 x 75s exposures at ISO1600
* Stacked using RegiStax 4
* Neat Image
* Photo Shop Levels
* Gimp Levels

I got a handful of images of M35 the other night. This is a beautiful open star cluster in the constellation Gemini (The Twins). This object is beautiful in even the most modest of telescopes. More aperture reveals a never ending number of fainter stars throughout the entire cluster. Smaller telescopes and binoculars however, may miss the nearby but much fainter NGC 2158 pictured to the left of the main cluster. At mag 8.6, the doesn’t just jump right out at you. My 6″ shows this in a subtle way, whereas my 25″ makes even this faint cluster look pretty impressive. If you find yourself under clear skies, be sure to look for the two bright stars of Castor and Pollux. The twin stars of gemini are at the head, whereas M35 is down near the leading foot. Checkout this star chart of Gemini for help in finding the cluster.

This image was constructed from (5) 60 second exposures at ISO400. As usual, I was shooing with the Canon Digital Rebel XTi at prime focus through my Astro Physics Starfire 160. For some reason, perhaps the location in the sky, tracking was much better than normal. I’ve not allocated the proper amount of time to make tracking a complete non-issue. I’m still limited to 60-120 seconds before star trailing becomes unacceptable. As the phase of the moon grows in the days ahead (and if/when clear skies return to Park City), I hope to finish this off once and for all.

These images were stacked using RegiStax 4 and were then manipulated inside PhotoShop. I used the levels function to set the black point appropriately and then used the Curves function to bring out some of the fainter details. I had to pull this into The Gimp, because on my Windows Vista machine, many of my software applications provide only limited and/or sporadic functionality. I’m currently in the process of upgrading to Ubuntu Linux. This should alleviate the multitude of pains I’ve been suffering through these last several Vista-Inflicted months. For those of you who are not familiar with it, The Gimp is a full featured, FREE, image processing software package. It is comparable to the pricey Adobe Photoshop in many ways. As I’m not familiar enough with either of these packages, I’m currently unable to give a good comparison. Anyway, its free and highly functional.

I mentioned previously that I’ve been reading through Ron Wodaski and Russ Croman’s Zone System for Astro Imaging book. This (still a read in progress) has given me a much better understanding of the principles needed to develop high caliber astro-images. It’s amazing to see details that I’d otherwise miss come into clear view by applying these principles. This book is a must read for the aspiring or experienced astro photographer.

Astro Photo Details:

* Designation: M35
* Type: Open Star Cluster
* Constellation: Gemini
* Magnitude: 5.1
* Size: 30′
* Open Star Cluster NGC2158 appears to the upper left

Astro Photo Processing Details

* Canon Digital Rebel XTi
* Astro Physics Refractor
* 5 x 60s exposures at ISO400
* Stacked using RegiStax 4
* Neat Image
* Photo Shop Levels & Curves

Ok, I finally got my image cleaned up. I also had the opportunity to crack the binder on a new book focused on image processing… from an astrophotographer’s perspective. It’s called “The New Astro Zone System for Astro Imaging” by Ron Wodaski with Russ Croman. I’ve only gotten a chapter or two into the book and feel like I’m 100% better at image processing. I can’t even say that I’ve taken in all that I’ve read… only a small portion of it… and yet…. as the accompanying image shows, I’ve certainly picked up something If you’re at all serious about astrophotography, this book is a must read. You may already know a large chunk of what’s covered in the book, but if you pick up just a few nuggets, this book could push you to the next level.

Anyway, this image was created from (10) 60 second exposures at ISO400 with Canon Digital Rebel XTi through my Astro Physics Starfire 160 at prime focus f/7.5. The images were stacked using RegiStax (another program that I’ve only scratched the surface with).

Next, I brought this into PhotoShop where I applied some of Wodaski and Croman’s magic. I used Levels (which I’ve used extensively before), and Curves (which I’ve hardly ever used before because I didn’t know what in the world I was supposed to accomplish with it). I used each of these twice and then saved the image.

Finally, I pulled this image into Neat Image. This is a program that bills itself as the best noise reduction program on the market. Not knowing much about this… and being satisfied with the results… I’ll accept their claim at face value. Neat Image took off some of the rough edges in my image. It considerable reduced the noise (pixelation) in the image with a somewhat intuitive interface. I’ll need to go through the docs to see what can be accomplished with this tool, but its interface was not the slightest bit intimidating… and seemed to suggest that I tweak settings to see the effects.

All in all, I think I have already made a qualitative breakthrough in my astrophotography skills. I’ve printed a few of my favorites… and am looking forward to revisiting some of my earlier efforts as I upgrade my skills with the aforementioned tools.

Be sure to checkout my earlier effort on Irregular Galaxy M82. This was created before I began working “in the zone”

Astro Photo Details:

* Designation: M81
* Type: Spiral Galaxy
* Constellation: Ursa Major
* Magnitude: 6.9
* Size: 21′x 10′

* Designation: M82
* Type: Irregular Galaxy
* Constellation: Ursa Major
* Magnitude: 8.4
* Size: 8′x 3′

Astro Photo Processing Details

* 10 x 60s exposures at ISO400
* Stacked using RegiStax 4
* Photo Shop Levels & Curves
* Neat Image

Among the best known galaxy pairing in the sky are M81 & M82 located in the northern constellation, Ursa Major. These two are particularly photogenic. M81 being a beautiful spiral galaxy while M82 is categorized as an “irregular galaxy”. Looking at the accompanying image of M82, its easy to see what it was categorized that way. First up, it doesn’t display any of the classic galaxy shapes. Not really a spiral galaxy, not really an elliptical galaxy, it hardly even looks like a galaxy at all… more of an anomaly. As you look at the galaxy, the first thing that catches your eye is the distinctive mottling through the center. There certainly seems to be a whole bunch going on in there…

Ok, so the post is galaxy pairs… what happened to the other member of the pair, M81? Well, while processing the image, the right half of the image which contained M82 suffered a number of aberations. I was too tired to fix these while trying to get a post written. Plus, I really liked the way that M82 turned out all by itself. So, I brought the image into Photo Shop and copied M82 out into its own file. I’ll get the image properly processed and added to another post at some point

This image was created from 12 images capture on the night of 11/3/07. This was a pretty nice night. 665 on the clear sky clock. Perfectly clear, Perfectly transparent skies, very steady skies.

Astro Photo Details:

* Designation: M82
* Type: Irregular Galaxy
* Constellation: Ursa Major
* Magnitude: 8.4
* Size: 8′x 3′

Astro Photo Processing Details

* 12 x 60s exposures at ISO400
* Stacked using RegiStax 4
* Photo Shop Levels
* Neat Image