Making A Stargazer’s Lantern

The official date for (Inter)National Astronomy Day was today, May 14, 2016. The astronomy club to which I belong celebrates on Memorial Day weekend instead, since the weather in our region of the world is consistently poor from mid-April to the beginning of May. However, I wanted to do something for the occasion, and while shopping at the local Menards for Shop-Vac replacement parts, I stumbled upon Coleman’s Soft Glow Table Lamp.


I thought it would be a good project to turn this into an astronomy-friendly red lantern. How hard could it be? The thing cost less that $20, so I threw it in my cart.

How to make it red? A quick Google search gave me the idea of using the flexible, squishy “gel” material from which decorative window clings are made. A stop at Hobby Lobby netted me a “Fourth Of July” pack of small clings — including a few red stars! Of course I laid down the $3 for that, and went home with my goodies.


Once back at the ranch, I unboxed the lamp, admired it for about ten seconds, and then immediately set about taking it apart. It was fairly obvious how to do so once the (empty) battery pack was removed: there are four cross-head screws that mate the base to the large white shade. So, time to gather all the items so I can work efficiently (I’m also a big fan of mies en place when cooking).


I found out a few things that you’ll want to know if you try this yourself:

  1. You’ll need to use a slightly-small Phillips screwdriver with a shaft long enough to reach the screws in their recesses.
  2. You don’t have to remove the screws completely to free the white shade from the base.
  3. There a small plastic spacer that lies behind the power button membrane on the front of the upper shell; it will probably fall out when you take the lamp apart, so just make sure you keep it safe. In my case, I kept it in a drawer until I was ready to reassemble everything; a reflexive behavior learned by living with thieves cats Elsie.

I decided to use both of the small red stars to get a deeper red, and used a square of clear packing tape to simultaneously squish them against and secure them to the LED and reflector assembly. Be sure to use a square of tape large enough that the edges wrap around the edge of the shield, to make it extra secure.


After that, it was a simple matter of putting the shade back onto the base, and tightening the four screws to mate the two together again.

Putting in the battery pack (now fitted with 4 D-cell batteries) allowed me to test the lamp. And, amazingly enough, it worked great right off the bat! I prefer the lower brightness setting for personal use, but the brighter setting will be good for public events.


There are a few irregularities in the illumination of the shade near the bottom — there were some crinkles in the tape that appeared as I formed it to the round shield. I suppose I could cut out a circular piece of tape and replace what I did, but I doubt I’ll ever get around to it. For $23 and about 10 minutes of time, I’m quite happy with the results, and I expect this lamp will see a lot of use on the deck and in the field for years to come.

The Everyone Tripod

Everyone Tripod Snapshot

The universal cure for shaky telescope tripod legs? I’m going to find out this weekend!

I’ve just created a page to house my design information and thoughts on what I’m calling The Everyone Tripod. It’s a design project that’s been literally years in the making, as I’ve used countless telescopes that were pretty good except their tripod legs were flimsy. With the acquisition of the incredible $199 Costco exclusive Celestron Nexstar 102GT, however, I decided to do a little recon at the local Home Depot and see what was available. After noodling a bit, I mocked up my design in SolidWorks and this weekend I’m putting it together. I’m pretty excited because so far the cost is $40 and everything but the spreader and the leg slots are available from my local Home Depot (they cut the leg pieces to length for me in seconds at no additional cost). You can find the details on my dedicated project page.

The One That DIDN’T Get Away

The Original Celestron C6

The original Celestron C6 was a Polaris-mounted 6" f/5 Newtonian.

A few months ago, I wrote about the Celestron C6 Newtonian reflector that was produced by Vixen back in the 1980’s. It was the third of four “classic black Celestrons” that I remembered from when I was a kid, and unique in that it was a wide-field telescope in contrast to the Firstscope 80, C4.5 and C8. While my early attempts to acquire one were unsuccessful, a few months ago I did win an eBay auction for a C6 optical tube assembly.

It arrived without a finder or a front endcap, but I’ve got a friend who may part with her original 6×30 finder from her SP-C6, and heavy-duty shower cap functions as an effective tube cover. There are a few small nicks in the paint, and two small holes where a Telrad base was mounted, but a little touch-up will fix those tiny cosmetic issues.

I’ve had a lot of fun tinkering with this scope (mostly in the garage and the driveway so far), and I’ve learned a few things.

The first thing I’ve learned is that the Polaris mount is more than adequate for this telescope. I really can’t think of a reason why Celestron switched this scope from the original Polaris to the much-heavier Super Polaris mount, other than increased profits in a more astrophotography-ready package. I’m thinking the astrophotography-profit angle here because there were optional dual-axis drive motors available for the Super Polaris, they could charge more for the heavier mount itself, and the 6″ f/5 OTA has a constant-distance “sled” focuser with a generously-sized secondary mirror which would appeal to shutterbugs of the day. At any rate, for visual use, the Polaris mount is simply wonderful. Even without a  second counterweight and the scope being woefully out of balance, when I lock it down, it doesn’t wiggle. At all.

It's easy to drop the rear cell from the C6, just like it is for the C4.5 -- once you know how. That makes it easy to center-spot the primary, which is necessary for collimation.

Another thing I’ve learned is that Vixen really did a great job on their Newtonians. Just like the C4.5, the C6 primary and secondary mirrors are easy to adjust. In fact, this scope practically invites collimation! It was a simple matter to drop the back half of the cell and center-spot the scope, and once I had a proper reference, the scope was collimated in a matter of minutes. The only plastic on the scope is the single focuser knob, and the rack and pinion gears of the “sled” style focuser. I’m told that those plastic gears are the only real points of potential wear and failure on this scope; everything else in the focuser is aluminum. Oh, if they just used brass for those two little parts instead of plastic! If I ever have problems with the plastic gears in the focuser, that’s what I’ll use to replace them.

I also learned why they don’t make threaded declination shafts anymore. These were super-cool-looking on the giant yellow Byers mounts that graced the 1960s and 1970s Questar-12 ads in Sky & Telescope. Perhaps in an attempt to enhance the precision feel of the original Polaris mount, the declination shaft is, in fact, a single length of 16mmx2.0 threaded rod. It does look great, and makes it easy to fine-tune the counterweight position. However, it also makes it a major pain to move the counterweight any significant distance, and taking the counterweight off the declination shaft for portability is more trouble than it’s worth. For the C4.5 OTA, there’s only one counterweight and it’s not a big deal to move the entire thing — mount and scope —  around because it’s so lightweight. I’m thinking the second counterweight is going to be around 8 pounds to accommodate the larger C6 OTA, so that’s going to make the overall setup noticeably heavier. It’ll be easier to remove the entire declination shaft for transport, should it become necessary.

As a side note, what you see in the picture is indeed a 25mm Plossl of the old Celestron “silvertop” variety. I’ve collected several Celestron silvertop Plossls over the decades, and all but one are red-lettered Vixen models of the same vintage as this scope. When I get that second counterweight made to allow for less dangerous use of the C6 on this mount, I plan to use the silvertops exclusively; in my limited testing so far, the vintage Plossls have been surprisingly good. A 16mm Nagler Type 5 might sneak onto the focuser once in a while, though…

The One That Got Away

"Newton would be astounded!" was the marketing phrase for original C6. Umm...yes, I think he would have been.

In the past I’ve talked about how much I enjoy classic black Celestron telescopes. Well, there is one telescope from that vintage that I’ve always admired but never owned: the Celestron Super Polaris C6 (SP-C6). This was a Vixen-manufactured 6″ f/5 Newtonian on Celestron’s Super Polaris German Equatorial mount — a heavier version of the excellent Polaris mount. In fact, before the SP-C6, Celestron offered the C6, which was the same optical tube assembly (although painted funky orange) coupled with the Polaris mount.

Anyway, about a month ago I was idly pursuing eBay on my iPad (yes, looking at used telescopes on eBay, Craigslist and Astromart constitutes recreation to me) and a few posts caught my eye: somebody had an SP-C6, and was selling it in two lots — the mount and the optical tube. The prices were very reasonable, as they often are a few days before auction close.

Hmmm…what to do? The prices were too good, so I put in a bid on each. It lasted about a day, and then I was outbid. I decided that I would mount the C6 tube on the Polaris mount, so I dropped out of the SP bidding and upped my bid on the C6 … which lasted for about two hours. Then, I upped my bid one more time — at this point I was still getting this OTA for under $150 with shipping — and went to bed hopeful I would win the day. But of course, I was outbid again a few hours before the auction closed. At that point, I made the decision that I didn’t want to go any further, and let it go. Still, it hurt a little bit to see the notification that I lost when the auction finally ended. That SP-C6, or even a C6 setup, was still on my mind.

Have I learned anything from this? Yes — at this point, I’d have to say I’m a telescope collector as much as an observer. I love to observe, and I love to teach astronomy and do public outreach, but I also am hopelessly enamored with telescopes themselves. Not really cameras, computers and electronics, but the telescopes and mounts themselves, their history and their varied design.

This one was for sale, but in the Phillipines -- I think the shipping charges would have been a little too steep!

My wife will probably read this and tell me this isn’t news to her. But after this latest episode, it dawned on me that some of the telescopes I have are there just because I like them, and I felt a little guilty about that. But then I realized that people collect guns, cameras, motorcycles, cars, Faberge eggs, and all sorts of things. So I got over it.

Now, if anyone has an SP-C6 out there that they are tired of, let me know. Or if you have an old Meade 6600 OTA, that would work too … I have the mount already …

The Nexstar 5

Most of the classic telescopes I own are decidedly not GoTo. Maybe it’s because I grew up in an age where even PushTo telescopes were rare (in those days, we called those contraptions “Digital Setting Circles”). Perhaps it’s because the first serious telescope I had was a 10″ Coulter Dobsonian, and I just got very comfortable with star hopping. In any case, I have little patience for the ponderous and noisy systems of early “classic” GoTo scopes (which is why I’ve never had any desire for an LX200 or Ultima 2000).

And yet…there is the Nexstar 5. The original. One of the early GoTo telescopes, and the grand-daddy of the long Nexstar line which extends into the present day. Why do I like this telescope so much? And why on Earth did I buy it twice?

My experience in mechanical design may have something to do with it. I’ve been in the MCAD game for 19 years, and in my work I’ve met hundreds (more probably thousands) of engineers and designers. I have great respect for what these folks do. I’ve felt their pain and reveled in their triumphs on numerous occasions. Over time, I came to recognize design trends in consumer and industrial products, and I could tell that contemporary telescopes of the day were warmed-over, slightly updated versions of old designs. Sometimes the only thing that was new on a “new telescope” was the paint job and model name.

The Nexstar 5, however, was a breath of fresh air. It wasn’t an evolution of the same single-arm mount from years past; it was a complete redesign. It looked good — really good. And it turned the heads of many astro-magazine readers, including mine.

When I stepped into the Eagle Optics showroom those many years ago, I saw it in person and instantly fell in love. It looked so cool. I immediately pictured it on the bookshelf in my living room, like a souvenir brought back from a trip onboard Jean-Luc Picard’s Enterprise-D. I started thinking:

It had almost the same aperture as my trusty RV-6, but this was so much more portable. I could take it on an airplane to Australia, if I went there someday. It has to have a better GoTo system than the old Tangent-based systems — the hand controller is totally different. And, it would also be my first SCT. Gotta have at least one, right?

I purchased the telescope on the spot, and for the next week I had a few clear nights to use it. It looked awesome in my living room. But under the stars? It just didn’t seem to have any punch. I like planets and globulars, and they seemed soft. After that one week, I boxed up the whole thing and took it back to Eagle Optics. They graciously and cheerfully refunded my money, and that was it.

Years passed. Other telescopes came and went. But one evening while perusing Astromart, I came upon a sweet deal: an original Nexstar 5 (not the N5i which was the current incarnation) with JMI fitted case, dew shield, 30mm Plossl eyepiece and tripod…all for a quarter what a new setup like that would cost. My thoughts went back and forth between my previous experience and that ad:

It does look very cool. With the case, it’d be truly ready for travel. And maybe the first one was just a bad example, optically. And wow it looks really cool. Gotta pay with cash, but I have a tax refund that would more than cover it.

I decided it was fate. The response was sent, the deal was closed and scope was delivered inside of a week. What happened next? You’ll have to read about that next time.

Classic Black Celestrons

Over the past several years, I’ve acquired a pair of Celestron telescopes from the late ’80s and early ’90s, along with some parts and time to “restore” them. Now I’m about ready to use them in earnest, and I think they will be a great pair for outreach events. Let me tell you about them.

Celestron C4.5

Purchased for $75 from Craigslist -- several years ago.

The first telescope of the pair is a Celestron C4.5. This is a Vixen-made 4.5″ f/8 Newtonian on the wonderful Polaris German equatorial mount. I purchased this instrument several years ago from a lady on Craigslist, who didn’t know much about it except that she wanted to get it out of her basement. It needed a lot of cleanup, and I left it stored in pieces after the last round of work on the scope. Recently, though, I put it back together and am now patiently waiting for some good weather to really put this instrument through it’s paces — everything is top-notch on this scope, except for the run-of-the-mill 5×24 finder. It didn’t come with a clock drive, and the original units are long gone from production and hard to come by on the used market. Fortunately, the modern Celestron/Logic drive will bolt right onto the mount and provide RA tracking with just a 9v battery; it’s a no-brainer at $35 and it will arrive soon from Hands On Optics. Until then, the slow-motion knob works well for manual tracking. I took a look at some nice sunspots just today with the included 25mm Celestron Orthoscopic eyepiece and a 5″ Thousand Oaks filter I already had for the old Nexstar 5 (another story for another time).

Celestron Classic 8

Celestron Classic 8 from 1992. Bought used at a swap meet in 2010.

The second telescope of the pair is a 1992 Celestron Classic 8 on the heavy-duty tripod of the day (this was purchased at a swap meet last spring and so I know more about it’s history). I power the AC clock drive from a jump-starter battery pack and a small inverter I had laying around in the garage, and the tracking is very good. Last year I used it a few times for sidewalk astronomy at Bayshore Town Center and it worked out very well. In fact, with the tracking I found myself with more ability to interact with people in conversation while they looked through the telescope, because I didn’t constantly have to interrupt by asking “is it still there?” or moving them away to re-center the object for them. We never have a problem with dew at Bayshore, probably becuase of all the heat from the sidewalk, road, and nearby buildings, so I never had to use a dew shield. Optically, the scope seems to be a winner as well, so much so that I tried using it in the backyard a few times last summer. That 6×30 straight-through finder was a pain to use, though, and I thought to myself I”ll need get a different finder for deep-sky work. Back in the grass, the dew situation was much worse as well. A simple $25 dew shield will help with that (coming in with the Logic drive from Hands On Optics). As for the finder, I managed to acquire the Vixen-made Celestron 8×50 Polaris finder at last month’s swap meet (one year after getting the scope itself), which has now replaced the original 6×30 finder. I’m thinking that 6×30 finder might make it’s way onto the C4.5, but that’s a project for another day.

Why do I care about these telescopes? What’s the fascination? Well, these scopes represented modern chic in telescopes “back in the day.” I graduated high school in 1989 so both of these instruments stand out in my memory, and appeal to me greatly. Maybe this is my version of a mid-life crisis…I don’t know. But they are a LOT cheaper than a sports car! The fact I was able to rescue them for very reasonable prices (the C4.5 was almost free) and put them into service again is just a wonderful feeling. Using them for outreach, they will introduce hundreds of people to the wonders of astronomy each year. Using them under the dark skies of Harrington Beach, they will take me back to my youth. Simple and effective telescopes such as these have no expiration date.

I prefer star hopping with small scopes, especially in outreach situations, but tracking will allow me to run both scopes at the same time. The dual “classic black” Celestrons should be an awesome pair in this regard. Plus, I think they look really cool and will attract attention on the sidewalk. We’ll see next month when the sidewalk astronomy season begins!