M45

As you may remember, I had my telescope out at the time of writing last post. At that time I already noticed that I was too late to get an awesome image of the Ring Nebula, I took better photos of the Dumbbell Nebula at different settings and tried to capture some Pleiades nebulosity. While working on last post, I was waiting for clouds to pass over, but eventually, they didn’t.

I think I’d better postpone my efforts to capture a glimpse of the Horsehead and Flame Nebula untill the Orion constellation is higher, somewhere in December, Januari… Apparently I live in an area where amateur astronomers are being terrorized every evening by foggy skies. By the time deep sky objects in Orion are high enough to be imaged, fog has already kicked in.

Nevertheless, as I mentioned, I also shot some decend images of other objects. I started with the Ring Nebula. But after my first test image, the photos became too faint because the roof was partially obstructing the view. The single frame I did get turned out quite nice by the way:

A single frame of the Ring Nebula.

When I manage to get more and longer exposures of the ring nebula, it should display more yellow and red features.

As quickly as I found the Ring Nebula, it took me over 10 minutes to get the Dumbbell Nebula (M27) in view. I took 12 good 15 seconds frames at ISO 6400 and 7 good 30 second frames at ISO 1600. The ISO 1600 frames showed less noise and stacked nicer so I used those to get the image below. I really like the amount of stars visible in the image. M27 is located in the constellation Cygnus which lies exactly over the star littered arm of the Milky Way.

Long exposure stack of the Dumbbell Nebula (M27)

My 5 stacked 30 second exposures of the Pleiades open cluster (M45) do finally show some faint blue nebulosity around the stars. Especially the lowest of the 6 brightest stars shows a glow with a well defined edge. The lines at the bottom right are the remains of an airplane saying ‘Hi’ while I was imaging.

Really faint, some blue nebulosity is visible in this image of m45. Especially the strokes that are caused by stellar winds.

After I finished my exams, I grabbed the first opportunity to get my camera out and shoot some pretty pictures. The icy sky in combination with the low sun friday evening, provided beautiful views. I tried to photograph them as best as I could:

Sun dog due to icy skies

Sunset over Enschede

The Enschede sky, shortly after sunset

Later that evening, I took my telescope out, including new mount, motors and feedback-loop guiding system. I never had the chance to use it before and I couldn’t wait to give it a try. The skies were definately not clear (a thin layer of clouds was still blocking light from the lower magnitude stars), but nontheless my guidecamera (my DIY xbox camera) managed to pick up some stars after playing with the settings for a while.

Modded xbox cam from side

The idea is, to have two telescope tubes aligned and both fitted with cameras. One camera functions as a guide camera and has the sole purpose of showing stars on the computer screen. The computer then sends signals to the motorized telescope to keep a selected star exactly at the same place on the computer screen. Since the two tubes are aligned, the second telescope – fitted with a proper imaging camera – has a perfectly steady image to photograph at long exposure times.

As a first star to try the system on, I chose Betelgeuse, a very bright, red supergiant. The system picked up the star and kept it in place for about 15 seconds. After that, it seemed to make one misstep and then lose the star. I will have a look at the settings and lower the step size to prevent overshooting while making corrections.

Luckily, I seemed to have aligned the telescope pretty well, so that the error was small enough for 10-15 second exposures without trailing. So without the feedback system, I could still make some reasonable photos. The first image is a single 10 second exposure of Betelgeuse and the stars around it.

First long exposure telescope image. The bright red supergiant Betelgeuse was my first target.

After that, I spend some time trying to find the Orion Nebula. This was quite a hastle since I couldn’t really see it, or the surrounding stars and I had to guess its exact location. Yes it was that clouded. Eventually, I found it and took a large amount of 10 second photos which looked like this:

Jpeg of raw 10 second image

Using 16 of those frames and stacking them together with 8 dark frames (photos with the lens cap on, to measure the noise induced by the camera temperature), I got the following result, which I’m quite pleased with 🙂

M42; Great Nebula in Orion. A stack of 16 10sec frames at iso 6400

I sure have seen much better images, but considering that my guiding wasn’t working yet, the orion nebula being very low above the horizon and the layer of clouds present, this image is very acceptable. Because by then, it was already late and the skies weren’t that clear anyway, I decided to try one last target and call it a night. The target I chose was M45; the Pleiades open cluster with its blue glowing stars. The image below is a single 20 second frame which I processed a little. The glow if visible due the the gas that surrounds the stars and reflects the blue light. This type of ‘nebulosity’ is called a reflextion nebula. In contrast, the Orion nebula is an emission nebula, that gets its glow from very hot gas that actually emits light.