The problem with consumer goods is that at the designers are not you. Everything is always a matter of trade-offs. The decisions that other people make for you might not be the ones you would make for yourself.
I bought a new telescope to use in the backyard. As vice president of the Austin Astronomical Society, I invited Scott Roberts, the CEO of Explore Scientific, and Stuart Parkerson, publisher of Astronomy Technology Today, to be our guests for a panel discussion. Ahead of that, I shopped at Explore for my next backyard instrument. They answered three emails and then asked me to call them on the phone before I was a customer. And they talked me out of buying extra oculars until I used the telescope often enough to judge better what would suit my needs. I was impressed.
The Explore Scientific First Light 102-mm refractor ($279) is a good instrument. Placing aside my cognitive dissonance, I made some minor modifications.
Because the objective lens is so large and heavy, the telescope does not balance in the center of the dove-tail receptacle. It balances almost full-forward in the grip so that the ocular has more moment arm, like a child on a see-saw balancing a grown-up.
The objective still has a tendency to dip into the tripod, so I attached two strips of foam under the front.
The XYZ control is a single lever that I found too short. So, I added 6 inches of plastic tube to bring the control closer to the focus draw adjustment wheels.
29 October: I removed the extension. It was too much leverage. It is easier to control the alignment by holding the frame. The action is still very tight: won't go--won't go--won't go--too far! I now know that I personally prefer gear-driven tracking.
The only other payment for the price is that the very artistic mount has the elastic stability of a thin plate. Fortunately, it damps out quickly.
The optics are good. The 102-mm (4-inch) objective brings in Jupiter, Saturn, and Mars well enough. The 660-mm focal length works best with my 17, 13, and 8 mm oculars. When the weather clears, I will use the Moon to try my 32-mm and the new 25-mm eyepieces. The final test will be the Pleiades, over my neighbor’s treetop after midnight and on the zenith before 03:00.
I was never satisfied that I had properly collimated my Celestron 130 EQ reflector. After a final round of stargazing and finding Albireo on my own, I put it all back in its shipping cartons and stored it in the garage along with the Meade 10-inch Schmidt-Cassegrain telescope (SCT) that I have on loan from the Austin Astronomical Society. (I took that one out just once; and at 65 lbs to my 68 kg, I found it inconvenient.) I bought a used 8-inch Meade LX Classic SCT from the club. The circa-1995 on-board computer did not work, after being repaired twice. They asked $250 and I countered with $325. It was a nice scope, but the right ascension (XY-left right) locked up and I did not want to take it apart. So, I gave it to the Goodwill. They will fix it, pass it along, and make some money.
My go-to scope has often been a 70 mm National Geographic refractor that I bought used from some kids down the street. They got it for Christmas and by July had lost the eyepieces, the cellphone adapter, the center plate, and the control rod for altitude (Z-up down). And the dew shield was jammed on backwards. (For all of that, they had never used it outdoors.) But it was a National Geographic brand; and I tested it on the street, and the objective seemed OK. It takes the standard 1.25-inch oculars. And it is an f/10 with a 700 mm focal length, which works well for higher magnifications: 13-mm ocular with 2x Barlow for 108x. So, for what it is, it has served me well in the backyard. But after three years, it is held together with rubber bands. So, I went shopping for a new go-to 'scope. The best thing about the Explore First Light 102 is the word “light.” All together I can carry it with one hand.
PREVIOUSLY ON NECESSARY FACTS
Problems with Pop Sci from Sky & Telescope
Physics for Astronomers: the Works of Steven Weinberg
The Asteroid Hunters by Carrie Nugent
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