Why Technology?

If you ever wondered “Why technology?” in the context of education, this will convince you.

ELS at Rupley Elementary from CCSD59 on Vimeo.


A few test shots with the new modified T3i

These are all single exposures. I’ll shoot calibration frames and do stacked images the next time I go out. I didn’t have much time for this shoot so I wanted to get a few different targets to get an idea of what this camera can do. You can really see how the reds show up. That’s what the modified sensor is supposed to capture.

You can click each photo for a larger version.

north america nebula

North America Nebula

trifid nebula

M20 – Trifid Nebula

lagoon nebula

M8 – Lagoon Nebula

omega nebula

M17 – The Omega Nebula

My Astrophotography Equipment

Because several has asked, here is my current equipment.

Camera Bodies

I currently own a Canon 6D and a modified Canon T3i. The 6D is my main camera for most things I shoot. It is full-frame and is the most affordable full-frame DSLR that I am aware of. For astrophotography I mostly use it for wide-field shots. Here is an example with the 6D.


Milky Way over North Georgia

The T3i for shooting deep-sky objects as it has a modified sensor that makes it more sensitive to hydrogen-alpha light. Objects like the Orion Nebula really pop with this camera. It also does a really good job with daytime shots, but it is a crop-sensor camera. I primarily use this camera with some kind of tracking when I want to shoot long exposures of nebulae, galaxies, and star clusters. Here is an example taken with the T3i.


North American Nebula


  • Bower 14mm f/2.8 manual focus lens
  • Rokinon 8mm f/3.5 fisheye manual focus lens
  • Canon 24-105mm f/4
  • Canon 40mm f/2.8 pancake lens
  • Canon 50mm f/1.4
  • Canon 135mm f/2
  • Tamron 150-600mm


  • Williams Optics 102mm APO Refractor
  • Celestron 9.25″ Schmidt-Cassegrain
  • Orion Short Tube 80mm Refractor
  • Celestron 90mm spotting scope


  • Orion Sirius EQ
  • Vixen Polarie

Summer is almost over. Thank goodness!!

Summertime is a weird time for astronomers. We love the objects in the sky, especially the Milky Way and wide variety of Messier objects we can find in or near it. But the downside is the weather. Lots of rain, and even when it doesn’t rain it gets very muggy and dew becomes a big problem. We only get a few dry days during the summer when viewing conditions are optimal, so we try to take advantage of those precious nights. Here are a few shots I was able to get this past summer.


Summer Milky Way

Eagle Nebula

Eagle Nebula


Lagoon Nebula


Copernicus Lunar Crater


Comet C/2014 E2 Jacques


Cygnus Region. North America Nebula at bottom-left.

A Nice Surprise

One of my photos has gone viral. Sort of.

I took this photo back in June where there was a nice conjunction of the crescent Moon, Venus, and Mercury. I posted it on my Flickr site and it got about a hundred views.


But a couple of days ago a Reddit user named tombh photo-shopped the Andromeda Galaxy into the photo in such a way that showed the galaxy if it were brighter. Here is that version.


There was an interesting discussion on Reddit about it here.


I thought the interest in the photo had died down, but I was very pleased to see that Phillip Plait had seen the photo and even wrote a nice article on his blog and credited me.


I can only say that I am glad my photo was used for this very interesting discussion. I used Creative Commons licensing on my images, and this is one of the reasons I believe in Creative Commons. The photo now has over 3,000 views and I am grateful for the credit that was given both on Reddit and by Dr. Plait.

A Cool Night at Brasstown Bald Mountain

Brasstown Bald Mountain, located in northeast Georgia, is the highest mountain in Georgia. Not only is it beautiful during the daytime, but the night skies there are very good because of the lack of light pollution. The nearest towns are Blairsville, Young Harris, and Hiawasee, but they don’t generate enough light to cause much a problem when shooting up at the mountain. There is a large parking lot where you can set up you telescopes and/or cameras, and it is one of my favorite places to shoot.

Last Friday night (November 29th) I saw that we would have clear skies in the area so I decided to pack up my scope and cameras and head up there for some night shooting. I got there just before sunset, and I managed to get a few really nice shots of that. This is my favorite of them:

Once it got dark, I decided to set up my Canon 60D on a regular tripod with a wide-angle lens and get some wide-field shots of the Milky Way. Here are my two favorites of that group:

I also set up my 80mm Orion APO refractor telescope and did some observing to get a feel of how good the seeing was. I then connected my Canon 60Da directly to the telescope and did some shooting of a few deep sky objects. The 60Da has a specially modified sensor that is designed for astrophotography. Here are the best shots I got with that camera connected to the telescope.

Dumbbell Nebula

Pleiades Cluster

I had intended to shoot a few more objects such as the Andromeda Galaxy and the Double Cluster in Perseus, but it started getting a bit windy. It was already very cold up there, and wind makes for bad shooting as it’s almost impossible to keep your equipment steady. I would up staying maybe four hours, and I got some really nice shots. If you are ever in that part of Georgia, I highly recommend a daytime or nighttime visit to Brasstown Bald.

Getting the “Reformers” on Board with Music

Maybe we need to try a new approach. Our so called “reformers” in education are so focused on standardized test scores that they won’t pay attention to anything else. This is so wrong. Our students are so much more than that.

So perhaps we try a somewhat subversive tactic. This study shows that music helps to develop cognitive schools that can be applied to other tasks. Well, if we can convince these “reformers” that studying music would INCREASE their precious standardized test scores, maybe they would begin to value music and perhaps other arts-education programs. Instead of cutting music programs, maybe they would start funding them again.

Okay, I know it’s silly to try to reason with these people but I thought this might just be a new approach.

Kennesaw Mountain as seen with the 50mm f/1.4

This is the 3rd installment of my project in which I take only one lens with me as I hike up Kennesaw Mountain. I have already done this with the 24-105 f/4 and 200mm f/2.8. I am really enjoying this 50mm lens, and here are a few photos from the shoot. This was the first time I have been up there since the leaves began showing some real color. I do wish it had been a sunny day, but I think the lens did quite well. The camera is a Canon 6D.

And here is a link to the entire set. – http://www.flickr.com/photos/srahn/sets/72157637167748814/

A New Project for Different Lenses

I’m doing a new photo project, which will also help with getting some really good exercise. I’m going to hike up and down Kennesaw Mountain several more times over the next few weeks, and I’ll be taking my Canon 6D with a different lens with me each time and only shooting with that lens. This past Monday I shot with my 24-105mm zoom lens, which allows for wide angle and medium telephoto shots. Here are a few photos from that shoot.

On Thursday, I took my 200mm prime lens, which offers more magnification but no wide angle options. It’s interesting to see how being forced to use a different lens makes you think differently about the shots you take. Here are some shots from Thursday.




Buck Bald and the Milky Way

I hadn’t seen the Milky Way for a while, and I saw that Saturday night was going to be really clear. I thought about going to my usual place, which is the Deerlick Astronomy Village, but there is a ton of construction of the Interstates right now and I didn’t want a 2 1/2 hour drive to turn into four hours or more.

So I decided to head up into the mountains. I know a couple of decent spots, but I wanted to go somewhere with really dark skies this time. I consulted my Dark Sky Finder app on my iPhone and saw that there was a promising area just over the line near Ducktown, Tennessee. That would still be a shorter drive than the normal drive to Deerlick, so I packed my cameras and headed north.

When I go into the area that I was looking for, I was having a difficult time finding a good place to set up. You need a large clearing without any lights nearby, and you also want to make sure you aren’t trespassing on someone’s property. I did find what looked like an abandoned sawmill right off Highway 68, but there was a really bright streetlight at one end. I could have set up so that I wasn’t right in the line of the light, but it still would have caused problems with some shots. I decided to continue on a few miles with the thinking that if I didn’t find anything better I could come back to the sawmill.

I drove about five miles and was getting ready to turn around when I saw the Coker Creek Village Retreat. It was late, but I saw that there was a lady out front. I decided to pull over and ask if she had a recommendation for me. Did she ever.

She told me to turn around and look for a sign that said Buck Bald Mountain. I had seen the sign earlier, but it looked like a driveway. She told me that there was a very wide open area at the top and that it was about a 2 1/2 mile drive to the top. She added that the road was not paved all the way and to not be in too much of a rush. I am very glad I took her advice.

I found the road and headed to the top. It was pretty bumpy for a lot of the ride, but it paid off. It was dark when I got to the top, but I could tell that I had struck gold. There is a 360-degree unobstructed view and hardly any noticeable light pollution at all. I started setting up my gear and as my eye began to adjust to the darkness the Milky Way began to show itself. The Moon didn’t set until about an hour after I got there, but it wasn’t very bright and it was not a problem as the Milky Way was in the opposite part of the sky.

I wound up taking only about 60 shots, which is not as many as I had done on other shoots. I felt like the quality was much better, and I left feeling very good about what I had. I was not disappointed when I get them onto the computer. I will definitely be returning to Buck Bald for future shooting. The next time I plan getting there in time to watch the Sun set. Here are a few photos from the shoot:

Sony A99

Canon 60Da

Canon 60Da with Fisheye lens

Here is a link to entire set. I will add more to it as I continue processing them.


My First Visit to the Tennessee Aquarium

I had a great time visiting the Tennessee Aquarium today. I had heard nothing but great things about it, and it did not disappoint. Of course I took a camera, and I decided to take my Olympus E-M5. It’s a small mirrorless camera and I’ve been using it a lot lately. It’s also a micro four thirds camera, and it has a 2x crop factor. So if I use a 20mm lens, it’s really like using a 40mm lens.

Here is a link to the entire set of photos from the visit.

Photographing an aquarium is not easy. You have to deal with a wide variety of lighting conditions. Some of the exhibits were in rather dark rooms, while others were like being outside. Also, since you’re looking through a lot of glass you will often have to deal with light reflections.

For this outing, I only used two lenses. One was my 20mm f/1.7 pancake lens. It’s really small and the large aperture makes for good shooting in dark conditions. The other lens was a 12-50mm zoom. The aperture isn’t very large, but in the brighter exhibits I was able to zoom in tighter than I could with the 20mm.

Here are a few of my favorite shots.

Purple Sun

I got a couple of interesting sunset shots on Thursday of this week. You can barely see the Sun in these as it is right at the horizon.

What I didn’t know was the science behind the purple Sun. But thanks to one of my Google+ buddies, I learned this:

The explanation for this phenomenon is that the CCD sensors used in digital cameras have their peak sensitivity in the infra-red – typically at a wavelength of about 1000 nm, which is well beyond visible spectrum of 400 – 700 nm. You can test the infra-red performance of your own digital camera by pointing a TV remote control at the lens of the camera from a distance of about 15 cm (6 inches). Most remote controls transmit infra-red at wavelengths of 850 – 1000 nm. Your camera viewfinder will probably show a purple light when you press a button on the remote control. The purple colour suggests that the red and blue sensors in the camera are sensitive to infra-red – but not the green sensor. Hence, the purple sun …..

Read more here! – http://atmospherical.blogspot.com/2007/08/purple-sun.html

Light and Shadow

This is from late afternoon as the Sun is casting some amazing red/orange light onto Kennesaw Mountain and into the quarry. The Sun was almost directly behind me as I shot this.

This was taken with my Olympus E-PL5, which is an amazing little camera. It’s a micro four thirds camera, and those are becoming pretty popular. I also have the E-M5, which is a bit larger. They both take fantastic photos and are good for “stealth” photography. Carrying a big DSLR seems to draw out all the wanna-be security guys who like to tell you how you can’t have such a big camera. These small body Olympus cameras are the size of most small point and shoot cameras, but their image quality rivals that of many DSLRs.

Some Fun with HDR

I haven’t posted in a while, but I’m going to try to do so more often now. We’ll see if that happens.

Anyway, we finally had some decent weather today in Kennesaw so I headed over to the quarry overlook and got some good shots. I decided to add some HDR effects to three of the photos. Here are the results.

I used Photomatix Pro to add the HDR.

Celebrating Copernicus and a Tale of Two Moons

Nicholas Copernicus is one of the most famous and important mathematicians and astronomers in history. It was he who surmised that the Earth and other planets revolved around the Sun. His birthday in February 19th, and I decided to honor him by photographing the moon which just happened to have a crater named for him in good view. The Copernicus crater is the prominent one at the bottom left of these photos of the moon.

Now see how much difference you can find in terms of quality of the two shots. I like them both very much, but one was taken with a full-frame DSLR (Sony A99) using a tripod and the other is a handheld shot using a point-and-shoot superzoom camera (Canon Powershot SX50). Can you really tell much difference?

Here is the shot from the Powershot

And here is the shot from the A99.

The first one is a bit “softer,” but not by much. I am honestly surprised at how good the first one turned out considering that I was not using a DSLR or a tripod. I was just walking to get my mail and I happened to take that camera with me in hopes of catching some good bird shots. I decided to take a few of the moon and the others were usable as there was too much camera shake. But this one turned out almost as good as the DSLR version on a tripod.

Now don’t get me wrong here. I LOVE my full-frame camera and it is my workhorse. But having a smaller one as a “carry around” camera is a nice thing to have, especially when it shoots quality photos.