Playing with my new 94 inch telescope

There is a story on the Internet about a guy who owns the biggest amateur telescope. He bought a 70 inch surplus mirror that was meant to go into a spy satellite, but became military surplus. He spent some time creating a huge truss telescope structure and apparently coated the mirror with some nonconventional method. I have no idea how good his mirror is and how good that telescope works, but reading about it threw me into a mood to go searching for another telescope.

I spend to much time dreaming about more telescopes, and more telescope mounts. Something I can take out to a dark sky site. My dreams often end up searching for things like mounts and large telescopes. Maybe a Losmandy g11 mount for Big Bertha, my ten inch Newtonian. Maybe some new planetary killer for sale on an astromart or cloudy night website. One moment it's a planetary killer, and another moment it's a rare large sct, perhaps a nine inch takahashi sct which is super rare and expensive, or a c11 with a hyper star lens. Or maybe a rich field telescope that is a little smaller than big Bertha that I could use on a tracking mount to take wide field photos when out at a dark sky site.

Then I get back to reality and think about the telescope I have access to at HJRO. It's difficult to compete with a Celestron c14 with a small personal telescope. Being at the observatory and able to look through the 14 inch telescope spools me. I often conclude, there is no point in spending money on another telescope which will not compete well against the C14, and cost so much time and money to deploy, I'd rarely see it used. I end up realizing I'm very fortunate to be in the FAAC club and able to look through the Lincoln Park Observatory Telescopes which are so close to home and quick to access.

If I had a lot of money, I could buy a huge telescope. I can dream of some monster telescope like a $75,000 50 inch telescope that one can buy from Great Red Spot astronomy. I'd have to wait for a mirror to be built, buy a trailer and then drive hundreds of miles perhaps to get a good view camping and observing. If I was to take photos they still would be limited because the tracking for a large dob of that size would not allow long exposure photographs.

If I had a huge telescope like these I'd have to schedule the time to take a decent photo, then download the photo and play with the photo using photoshop. And I might not select the right photos or it might be cloudy where my telescope was setup. I could rent a telescope from I telescope.com or some other rental site and spend money for imaging time.

But I already have a 95 inch telescope that I own (in part) as a taxpayer, it's sitting in orbit. It takes photographs of many interesting objects in space. It's the Hubble space telescope and NASA puts all the raw image data into files called FIT image files on the web. Anyone can browse and download any of the thousands of images that are posted and learn to process those photos. NASA even has programs on the web to help me convert a fit file into a readable tiff file inside photoshop and there are tutorials on the web that show us the basics of merging the separate filtered images into a color file. (I won't go into details but can post a link later.)

I've thought about this for years and never tried to process a Hubble photo until tonight. I decided to go out to the web and select an image and learn a little bit about how to process that image. My photoshop skills are still fairly basic.

I went out and selected the ring nebula. One of many photos that NASA has out there, a color three channel image fit file was selected and downloaded to my Macintosh laptop. I used fits liberator to convert it to a set of three tiffs representing three color channels.

The program created a three channel image which has three different color channels. I didn't spend time to read up and determine what the three colors were and probably made that mistake, not using or selecting the proper colors. I just guessed that layer 1 was red, layer 2 was green and layer 3 was blue : an rgb image. But that probably isn't the case with the image I selected from Nasa's site.

I processed the first attempt with r,g,b as the channels and merged them. I used curves on each channel to adjust them a bit and merged the three into an rgb image. Below is my first attempt.

Ring Nebula (green tint)
My first quick image process of raw fit file from at the Hubble space telescope.



As you can see there is a red and green tint to this image which is not true colors that we'd see. My curve mixing was pretty good on this image, for a first attempt. There is an error in the image I didn't mask out, but the nebulosity is pretty good in this image. The sharpness is stunning of course, thanks to the great source image NASA provided.

Not entirely happy with the colors I choose, I decided to reprocess it from the same fit file. I did this with red for channel 1, blue for channel 2 and green for channel 3 of the exposure I downloaded. This gave me a more true to natural color of the Ring Nebula, but I didn't process the curves as well brining out the subtle shades in the nebula that I was able to get with my first attempt. Clearly there is a lot more to learn.

As you can see the Hubble images provide a pretty stunning result. Quite a bit better than our c14, and it only took me a little bit of time in photoshop to get this image.


Ring nebula (closer to true colors) second attempt from Hubble image below.





The best thing about my new 94 inch telescope is, it didn't cost me a dime and the images are just sitting their on the NASA website ready to be processed.

(Compare the Hubble image with a single still we took of the Ring Nebula some years back at the Lincoln Park observatory.)


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