The Telescopes

Telescopes and equipment used in my Heavenly Backyard Garden.

I have always had an interest in astronomy since I was about 5 years old. As a child, my uncle bought my brothers and me a little 2 inch refractor telescopes which continued to evolve my celestial interests. While attending Murray State University, I was exposed to their 16" reflector scope in an observatory where we snapped color slides of Jupiter, my first taste in astrophotography. I even built a small 4" reflector newtonian scope while there. While here in Savannah, I did buy a Celstron Nexstar SE 6" Schmidt-Cassegrain. This was my first "Go To" scope where it is computerized to go to the celestial object of interest, providing you had it properly aligned. Shortly after my retirement as a broadcast meteorologist in 2015, I purchased the Celestron EdgeHD 11" Schmidt-Cassegrain telescope with the CGEM II equatorial mount. This is no small purchase, to say the least, but this is what I needed to do some serious astrophotography. I was glad I always like to workout at the gym because these scopes are heavy! The total weight of the rig for the 11" scope is well over 100 pounds. Since then I added a few more scopes and mounts.

The Celestron Edge HD 11 inch Schmidt-Cassegrain
This is the Celestron Edge HD 11 inch Schmidt-Cassegrain telescope. The primary mirror is 280mm (11") and the focal length is 2800mm giving it a focal ratio of f/10. This is an excellent scope for planetary observation. With the different accessories, I can change the focal ratio to f/20 or f/30 for even closer views of the planets. I can also reduce it to f/7 which makes it good for viewing nebulae, star clusters and galaxies. There is even an accessory called a "HyperStar" reducer which drops the f ratio down to f/2 for wide field a view observation and astrophotography. However, beware, these accessories come at a high $$$ cost. Since my hobby is photography, I only own one eyepiece as I rarely look through any of the scopes visually. All my viewing is on the computer screen via the attached cameras.

The Orion ED80T CF Triplet Apochromatic Refractor

Unlike the large Schmidt-Cassegrain telescope, this is a refactor scope with the main glass lens at the front with a triplet of corrector lens to correct the color aberration associated with single lens scopes. The lens is 80mm (3.15") with a focal length of 480mm resulting in a focal ratio of f/6. Unlike the big 11" scope that weighs 28 pounds, this one weighs only around 6 pounds. I am amazed at the clarity from this little scope.

The Orion 190mm f/5.3 Maksutov-Newtonian Astrograph
In between the two is this honey: The Orion 190mm (7.5") f/5.3 Maksutov-Newtonian Astrograph. This telescope is similar to the Schmidt-Cassegrain type but instead of reflecting the final image back through the mirror, the image is reflected up through the eyepiece on top of the scope at the front via a 45 degree prism. Similar to a reflector except has a corrector plate on the front of the scope. The results is a very clear and sharp image. It has a focal length of 1000mm resulting in a focal ratio of f/5.3. This scope is excellent for deep space objects such as nebulae, star clusters and galaxies targets.

Canon EF 70-200mm f/4L USM Telephoto Zoom Lens
You don't have to have a telescope to get involved with astrophotography, a good camera with a lens is a start. This is the Canon EF 70-200mm f/4L USM Telephoto Zoom Lens which you can attach to a DSLR camera or to a dedicated astrophotography camera. In this case, the lens is attached to a One Shot Color (OSC) CMOS camera. It's important to have a sturdy tripod. However, unless you have an equatorial mount to track the rotation of the earth, you won't be able to shoot longer than 5-10 seconds before you begin to see streaking or smearing of the stars. However, with these new 'stacking' programs, you can take several short exposures and them 'stack' them together resulting in a clean longer exposure image containing more detail.

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