Astronomy

While visual astronomy provides its own sense of fulfillment, capturing those amazing night sky visuals on a camera provides one with another kind of thrill. However, capturing photographs of the night sky is a whole another ball game and a bunch of investment in time and of course money 🙂

I hadn’t been spending too much time on astronomy/astrophotography and wanted to get back into it so I recently spent a whole lot of moolah in new gear. There were several reasons for my lack of time investment in astronomy/astrophotography : 1) my first telescope, an 8 inch Newtonian, was big and bulky for a quick set up 2) I was still getting my head around polar alignment meaning a whole lot of time spent just in getting the telescope set up 3) Newtonian’s require a lot of upkeep including collimation adding to the set up time 4) Pacific northwest weather did not give many opportunities for clear night skies 5) Life.

So, the first piece of gear I bought is the Explore Scientific 4 inch refractor telescope. While the scope is half the aperture size of my Newtonian, it is much lighter and bulky so very easy to carry and handle. The second piece was a planetary camera QHY462c and the third one was a 5x barlow. I rushed to purchase the camera and barlow specifically to capture Mars, which was soon going to be in opposition. Armed with the new gear, I set up in my drive way. Unfortunately, the seeing wasn’t as great on the two nights that I set up so extracting good frames was a bit challenge. With the PNW weather, you don’t get many nights in winter where the sky is clear. So those were the only two days where I got a good view of Mars from my drive way. I was able to capture the above image. I think it is not half as bad for a first planetary photograph!

While I am happy I was able to capture this picture, I think for planetary photography, my 8 inch Newtonian is better suited. Over the past several months, I have learnt a lot and I think am now better equipped to take my Newtonian out and quickly setup whenever I need to do planetary imaging. However, that would have to wait for a clear PNW night and planets showing up in the eastern sky to be visible from my driveway.

As every newbie amateur astronomer might have at some point struggled with polar alignment, so did I. In this post, I’d like to share an aid that I have started using that has helped me reduce my frustration and time required for setting up and aligning my telescope. Just FYI, I have spent many a wasteful dollar to get better at astro photography. Partly because I like to do things on my own and partly because I rush to try something to see if it works. I had initially bought the polar alignment scope from Orion. While useful, this aid requires that the scope itself is aligned. In the sense, if you place the scope on the mount and rotate the mount in the RA axis, the position of cross hairs should not move. I found that the scope I bought did not have this aligned. It required a lot of fine tuning to make sure that was the case (I don’t want to get into the details of that on this post). I used this for a few times but was not convinced that I was getting polar alignment right.

I researched a bit and and learnt about QHYCCD pole master. This device makes polar alignment a breeze. Please note that this is not very useful if you are a visual observer and do not carry a laptop with you for your astronomy sessions. This device gets you amazing polar alignment in the less than 20 minutes. Recently, I purchased a APO triplet refractor for getting into astro-photography and I before that I arrived, I wanted to test out my pole master given I was having issues with it when I tried it out last time around. I just took my camera this time to take some photos of Andromeda Galaxy with a tracking mount and pole master aligned tripod. I took few photos and one with six minute exposure. Given the warm night, the seeing was kind of okay. I will let the photo speak to the quality of polar alignment. This is an unprocessed single six minute exposure of the Andromeda Galaxy:

The slight trailing you see there can be attributed to the seeing and not polar alignment. I can say that with confidence because I saw this trailing even for a 30 second exposure photo. I had to squeeze this session in between my new born’s sleeping hours so wasn’t able to spend extended hours outside. While wrapping up my session, disaster struck – I dropped by telescope tripod mount. The stepper motor for RA axis got dislodged. I figured it out while trying to test out telescope control using Stellarium. I put the stepper motor back in place but haven’t checked if everything is working fine. I’ll need to check that when I get a chance again.

One of challenges for me making progress in getting better at astronomy and astro- photography apart from the fact that I live in Pacific Northwest (PNW) which has way too many cloudy nights, is the fact that back when I bought the telescope, I bought a 8 inch Newtonian which was way too bulky and complex for a newbie. While, I have gotten better and now no longer consider myself a newbie, the bulky equipment was still a challenge setting up, aligning, and collimating on cold PNW nights before actually getting into visual astronomy or astro-photography. In order to make things easier for me, I recently purchased a refractor telescope. It’s a 102mm triplet which corrects for any chromatic aberrations. It’s less than half the length and weight of my Newtonian reflector.

After I got it last week, I was eager to test it out and do visual observing to see how it compares to my old telescope. Since I have a 4.5 month old at home, it’s hard for me to be away for several hours at night so I decided to set it up in one of the rooms with a view of the eastern sky. In the last few weeks Mars is prominently visible in the Eastern sky which seemed like a pretty good target to view. I also got a QHY CCD guide scope and planetary imaging camera that I was interested in testing out. As the night fell, I quickly set up the telescope and tried to view Mars through the 25mm eyepiece. The telescope comes with 2 spacers to be able to adjust the focal length. To get a sharp image, I had to use one of the spacers. When I viewed Mars through it, the planet looked weird. It was as if there was a Bahtinov mask placed on the telescope. See below the picture that I took from my smartphone camera placed in front of the eyepiece.

I was concerned and reached out to the customer service to get this resolved. The agent, who was very helpful, thought I might need to collimation to get the lenses aligned. I was very concerned with this given what I read online about collimating a triplet refractor. He assured me that this was not a monumental task if I am familiar with collimating a Newtonian, which I was. I was getting mentally prepared to do collimation but were still exchanging emails about the problem. After some back and forth discussion and exchange of pictures of my set up and telescope, the agent suggested that maybe I should try to take the telescope outside given I was viewing through my window and screen. I thought it might not help but I said I will. I did some online research on effects of window and screen on telescope images. Turns out that temperature differences and screen can have big impact on what we see through the telescope. The screens actually cause a diffraction pattern which result in the image that you see above . Excited that this might be the reason for what I was seeing, I took the telescope out that same night and voila: crystal-clear views of Jupiter and Saturn.

I profusely apologized to the kind agent for sending him on a wild goose chase. Having a recent Master’s in Physics I should have figured that the screen at that distance from the source of light and the telescope was small enough to cause diffraction pattern. However, I was so focused on there being some misalignment on my telescope that I did not even think about it. While classroom learning as all well and good, as they say, experience is the best teacher.