First Light

celestronI packed up the Meade this afternoon. I’ve enjoyed it but it’s time to let someone else have an adventure with it.

The delivery truck came after dark (of course!)–and late in the day there were two brief but fierce bursts of snow. One minute, gorgeous gold late-afternoon sun painting the trees and the mountainside. Next minute, the dark side of Rura Penthe. However, by nightfall, the stars had come out along with a waxing crescent moon.

Though it was after dark and after dinner, I turned on the patio lights and carefully assembled the scope, piece by piece. Then I began what will be a long process of learning how to use this fine instrument.

I bought a Celestron Omni XLT 120. It’s a refractor with a 4.72″ objective lens (120mm). The focal length is 1000mm, over 39 inches. This yields a focal ratio of 8.33, a bit slower than my old Meade, which was an f/5.  (Divide length by diameter, and don’t mix your inches and centimeters.)

The glass isn’t ED, but it seems to be high quality, and is coated with the Starbright XLT coating, which enhances transmission. (For ED glass, I would have to add a zero to the price tag.)

The scope is substantial, the focuser smooth, and there’s nearly zero vibration when focusing or locking and unlocking the axes. Mount is solid.

I chose not to extend the tripod to its full height, partly because it was so praised for stability when unextended. As a result, there was a lot I couldn’t see, either because the scope couldn’t peek over the fence or I couldn’t bend low enough to see through the eyepiece. Tomorrow I’ll extend the legs. Unextended, the tripod is rock solid, but unworkable.

The eyepiece–I’d packed up the Meade EPs, so I was down to my 26mm and 4mm mid-price EPs, bought via Agena Astro. The scope came with a rather good 25mm EP, so I used that most of the evening. At 1 meter focal length, this yields a magnification of–divide focal length of scope by focal length of eyepiece– 40x. At this magnification, the moon neatly fills the eyepiece. (I want a 2″ eyepiece next.)

Finderscope is a nice 6×30, a step up from the plastic laser-dot I had before. (The laser finder is actually still in like-new condition, a surprisingly good piece of equipment.)

For a first light on a frigid night after dark, with some snow on the ground, I thought a short session best. I found a red star near Regulus, perhaps Alphard. I spent timer with the moon, and enjoyed a clear view of Almaak. Otherwise I just slewed here and there, getting the feel of the scope. Stars were quite sharp. I noticed a fair amount of false color around the moon. The colors of Almaak were good, with a real orangey note to the larger star.

I nearly bought a Maksutov from Celestron, but balked at the idea of being tethered to a computerized alt-az mount. I don’t want to web-surf the heavens. I don’t intend to google God. I’m in this to figure it out.

About Jon

Organist, sacred musician, teacher, writer, working in New York City and parts north. Amateur genealogist, astronomer, etc.
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