Author’s Telescope. Equipment. Used for This Book

The initial thought in the creation of this book was to use 100 % NASA produced photographs from full moon, to the zoom-in shots, to LRO photos, and to Apollo astronaut shots.

But as the book evolved, to produce the view that a backyard observer would see, it became a necessity and challenge to produce lunar photographs of the full moon and the telescopic views myself.

I own several telescopes that are capable of producing outstanding lunar images, and I initially used three refractors of mine: a 94 mm and a 130 mm Brandon apo – chromatic refractors, and a 102 mm Stellarvue 102ED refractor. Since refractors produce the sharpest and most contrast images, I felt the aperture ranges were representative of telescopes commonly owned by potential readers of this book.

The two Brandon refractors are legendary late-1980s telescopes and highly sought after, since at their heart are Astro-Physics triplet apochromatic objectives. Both Brandon refractors are mounted on Vixen German equatorial mounts, with the 94 mm on a 1980s vintage Super Polaris mount with right-ascension drive and manual declination drive, and the 130 mm on a Vixen Sphinx SXW dual-axis drives and computerized STAR Book control. The challenging aspect of using these tele­scopes are their somewhat archaic Unitron rack-and-pinion focusers, which for visual use are perfectly adequate, but for photographic use lacks finesse and made high magnification fine focusing challenging. Prime focus projection was used for full Moon photos using these telescopes.

The Stellarvue 102ED is a more recent late-2000s vintage, using modern low – dispersion ED glass and a two-speed Crayford focuser. The two-speed Crayford focuser facilitated fine focusing for the higher magnification photographs. Higher magnifications were achieved using Barlow lens projection in combination with extension tubes. The Stellarvue 102ED is mounted on a common mid-priced CG-4

German equatorial mount with dual-axis drives. Although the CG-4 lacked the sophistication of the Vixen mounts, the short exposures used in producing lunar photos did not require high precision or any fine adjusting guidance from the mount.

An affordable digital single lens reflex, or DSLR, camera was used. A Canon XTi DSLR equipped with the appropriate T-mount and T-adapter was used. Exposures ranged from as short as 1/800 second for full Moon shots to 1/60 second for the gibbous Moon. Initially, the photos were jpg-compressed, but as experience with the camera-telescope combination was gained, the RAW format was used to facilitate post-processing of the photos using RegiStax and Photoshop software.

In the end, I found the Stellarvue produced the best photographs, mostly the result of the combination of high quality optics with a excellent dual speed Crayford focuser. All of the author’ produced photos in this book are the result of several clear evenings during February and March, 2012 using the Stellarvue 102ED and the Canon XTi DSLR. Post-processing of the digital images were per­formed on an Apple iMac using Adobe Photoshop.

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