Astronomical Equipment

Binoculars: Orion Explorers. Inexpensive and rugged. There's a lot of reflection if bright lights are present -- the moon, streetlights, etc. Eye relief is good, and I cannot focus the binoculars without my glasses on. Orion sells larger binoculars (mini giants -- 8x63 I believe) which I probably would have gotten instead had I realized I could have held them steady, but I am very satisfied with the Explorers. They strike me as being a very good value.

I highly recommend getting a set of binoculars when starting out -- you really can do an amazing amount of stargazing with a pair, and the wide field of view makes it ever so much easier to locate stuff. Moreover, many extended objects -- star clusters, for example -- simply look better. There is a binocular buying FAQ out there, along with the telescope buying FAQ, which I found useful.

I also bought a Celestron Starhopper for my dad -- an 8" Newtonian. The Starhopper is a pretty cool scope. I would have bought the Orion DSE if I hadn't gotten such a good deal on the Celestron (the closed-mirror cell on the Meade, however, made it decidedly unattractive). The Celestron mirror mount is nice and cools quickly, and the dovetail sliders on the altitute trunions make balancing the scope a piece of cake. The secondary mirror is rather large and uninspiring, though, and is stuck on a single, very thick stalk. The stalk is not adjustable, and in this scope the mirror was not centered in the focuser. The telescope mount itself is also somewhat lame, in that the nylon altitude bearings and teflon/laminate azimuth bearings make for pretty stiff action, requiring jerks and tugs to e.g. track a planet. Finally, the dinky rubber feet just don't cut it.

To fix all this up, my dad and I have done a few upgrades. First, we drilled two holes in the focuser tube above the mirror stalk. We then threaded the holes and drilled through the sonotube -- now there are two screws which can adjust the position of the mirror stalk. By shimming the stalk with a washer, we were able to adjust it so that the secondary mirror is centered in the focuser tube.

The secondary mirror can rotate along the telescope tube axis, though. When the scope first arrived, the screw holding the secondary to the stalk was tightened all the way down, and the mirror pointed sideways! To get the mirror reflecting light straight up the focuser tube, we shined a bright light down the telescope. When the mirror pointed straight up the tube, the light came out as a solid cylinder, i.e. made a solid, bright circle on a piece of paper held outside of the focuser tube. These last two simple modifications gave _noticably_ improved performance -- brighter *and* sharper images -- in subsequent viewings, even to these amateur eyes.

To improve the altitude action we got a sheet of teflon (from a junk store) and cut some perhaps 3 inch strips for the altitude bearings. We just overlayed the strips on top of the old nylon bearings, and cut them long enough that we could attach them with screws on the top of the mount (i.e. the screws aren't underneath the altitude trunions). The altitude action is now quite smooth, making planet tracking much, much nicer at high magnifications.

Finally, to improve the azimuth action, we bought three _precision_ bearings and some metal rods (bolts actually) to mount them on. The plan is to cut out some holes in the bottom plate of the mount, for the bearings to sit in. The bearings will sit on the rods, and the rods will lie along a *radius* of the lower plate (i.e. draw a line from the center of the plate to the edge -- the rods lie on this line, the bearings lie perpendicular to this line), and will be attached using a pair of U-bolts on either side. Then the plan is to put a piece of smooth formica on the other plate, which will ride on top of the bearings. We believe this will give some mighty smooth action -- no more jerks!

Finally, we picked up some large rubber feet, again from the junk store. These will be attached more or less underneath the bearings, and we expect that this will improve stability and damp vibrations considerably.

Eyepieces and accessories

To complement the scope, I bought several eyepieces: a 32mm Celestron Plossl, a 9.8mm Meade plossl, and a Celestron Ultima Barlow. With the 26mm Kellner that came with the scope, this gives a wide range of magnifications. I chose the cheaper plossls over the more expensive super-plossl/ultima/etc. eyepieces, because I felt that several decent eyepieces was better than one expensive premium eyepice, and that I probably wouldn't notice the difference. I look forwards to comparing them with some more expensive eyepieces, to see if my reasoning was, well, reasonable.

The Ultima barlow seems pretty good, but I'm pretty sure that it is subject to internal reflections, and some vignetting, which can be annoying. Sometimes the image seems to dim more than it ought to. All three eyepieces perform well to these eyes. Around here, the air is pretty turbulent due to the mountains, so I don't see a lot of planetary details, and it remains to be seen whether higher magnifications will reveal more detail (the Barlowed 9.8 gives around 250x magnification). Nevertheless, I have so far seen the Cassini division using averted vision, cloud bands on Saturn, and wisps of clouds on Jupiter (still haven't seen the spot, though). I have easily split stars down to 4", but am not good enough at locating them yet to see what the atmospheric resolution is. I actually think I could see more planetary detail from Chicago, with less than optimal collimation.

I also got a Telrad to go with the scope. The cool thing about the Telrad is the sighting circles -- they are set at 0.5, 1, 2, and 4 degrees, which makes accurate starhopping possible. On the downside, I can't see faint stars when the LED is lit up, even when it is dim -- I think it's because my eyes have to focus on the near object of the LED rings. Anyways, without a finder scope I've been very unsuccessful at finding various deep space objects -- even when I find them in binoculars, I have trouble locating them in the scope. A finderscope is a must, in my opinion.

I also got the Orion basic color filter set, more recently. So far I have seen modest improvements on occasion -- time will tell if this was a worthwhile investment.

Finally, and most importantly, I got several books! H. A. Rey's "The Stars" is great! It's in the children's section of the bookstore. It is a *much* better guide to the constellations and the night sky than the other books I looked at. I also got the "Sky Atlas 2000" charts, field version (white stars on black background), and have found them useful. I also have "Using an Astronomical Telescope", by James Muirden, which I have found very helpful and interesting. I've got a few other books, but the other thing I reccommend is Sky and Telescope.

The total investment on all this equipment was substantially less than $1000. So far it's been very interesting and rewarding to use, and I expect that it will last for a long, long time -- a very good investment.

Last Updated: 2/10/99
Stephen Judd --