"We learn not in the school, but in life" - Lucius Annaeus Seneca
I need to stop shopping around Facebook Marketplace. It's a dangerous place for impulse shopping.
A decade ago, I made a couple of posts about some brief experiences with a nice amateur telescope and astro-photography
I just picked up an 8 inch diameter telescope with all the accessories for $500. It's a Celestron C8 Ultima, and it came with travel case, tripod, equatorial wedge, spotting scope, and a couple of different eyepieces - a Barlow lens and a Plossl lens. Quite the package for the money.
"The Ultima C8 (1988) had a number of incremental enhancements, including a rechargeable lead acid DC battery (later replaced by a simpler 9V battery) sturdier mount, and upgraded electronics. Later versions have PEC. Very desirable today if you don't want or need computers. Expensive for its time at around $2400."
$2400 in 1988 is about $6589 in 2025. Here is the inflation calculator that I used. Glad I didn't purchase that thing in 1988. Actually, I could not have afforded it back then...
As we all recall (LOL) from high school, the area of a circle is Pi times r squared. The radius of the primary mirror is 4 inches. 4 squared is 16. 16 times Pi is about 50 square inches of light gathering goodness, which is a significantly larger area than the pupils of your eyes, no matter how much LSD you ate.
The tripod needs to be cleaned up and waxed. It simply doesn't spread out due to years of non-use. The case is pretty corroded. The wedge needs to be cleaned, but the optics are in great condition as is the rest of the optical tube. It even has a piggyback mount for a camera.
One thing that I noticed is that this thing has a cord to plug the clock drive into a 120V AC house outlet. Fortunately I have a couple of small inverters and dozens of batteries that should easily run the clock drive in the base of the forks. The review above mentions "PEC", which is short-hand for "Periodic Error Control". This scope doesn't seem to have that. It may, I need to check under the fork base and see what kind of electrical connectors are underneath besides the AC power connection.
Below is the update of progress bringing this very nice telescope (nearly) up to the desired point.
Below: Scope and accessories in the beaten-up travel case.
Below: The tripod, which was quite dirty. The legs absolutely refused to spread beyond the point where they are stuck in the image.
Below: A few more images of the tripod before cleaning, lubrication and screw repairs.
Below: I removed the wedge from the tripod, took out all the short mounting screws and long adjusting screws, and scrubbed the thing off in the deep sink in soapy water. Then I dried it off and oiled all the pivot points. Two of the longer screws were significantly bent, so those needed to be straightened out.
Below: Top-down look at the tripod, with the wedge removed. It was a bit dirty, but after cleaning and lubrication, it opened up quite a bit better. There is still a sticky spot when deploying the legs.
Below: Tripod and wedge both cleaned and lubricated. Adjusting screws need further work.
Below: In both images you can see a bit of bowing in one of the adjusting screws. I of course overdid it removing the bowed screws in the hydraulic press and bent them backwards. In the end I put them in the vise and tapped them with a hammer until they were straight. It took quite a while beating and checking, then beating and checking.
The straightened-out long screws had enough corrosion - probably aluminum oxide from inside the threaded holes in the tripod - that I decided to wire-wheel them then plate them with nickel. It went pretty quickly and wasn't much trouble.
Below: Showing corrosion on the threads.
Below: A few pictures of the nickel electroplating process.
Below: The nickel plating container doubles as a secondary containment for the plating solution. It's carcinogenic liquid, so some care must be taken against a damaged jug.
Below, the final nickel-electroplated screws, following a quick buffing. There are brightening additives you can put in the electroplating solution, but I've not used them as yet.
Below: Straightened and plated screws back in the wedge. They went in smoothly and the T-handles weren't traveling in orbits as I screwed them in. Straight and smooth.
As mentioned previously, the travel trunk for this telescope is in rough shape. I have a new trunk on order through Amazon. The new one even has luggage pull-along wheels! 40 years of progress!
When you look through the finder scope, if the battery and LED bulb are working, you see something like this:
Most people have replaced the finder scope with a gun-sight type of reflex optics called a Telrad. I might move to this style if the old-school finder scope gets to be a hassle.
Below: A telrad style finder scope.
All three of the hex screws that hold the focusing knob in place were loose. The black ring that they secure in place was quite loose and I could hear parts inside the scope clunking whenever the optical tube went from vertical to horizontal. I hope that was just a bit of looseness in the focusing optics. It stopped once I got the screws for the ring tightened up.
Below: Hex key set for tightening the above screws. I was also trying to find a cover for the opening on the back side of the scope. When I bought it, there was a rag stuffed in the hole - and not a lint-free rag.
Below: Finder scope on the table and re-assembled. You have to take it apart to get it off the main telescope. I found some lens caps for it as well among the travel case accessories.
The telescope base comes equipped with a Byers clock drive assembly. Because the earth spins once every 24 hours on its axis, stars and planets will drift out of the field of view very quickly unless the telescope constantly spins in the opposite direction every 24 hours - thus the need for a wedge and a clock drive.
Below: I removed the cover from the Byers drive to ensure the worm drive was rotating, that there was no binding, and the grease wasn't dried out. I'm not a clock drive expert, but everything seemed tight - as in no slop in the gears - and normal.
I thought it was odd that the clock drive uses 120V AC power, because most people (in 1988) were probably going to haul this out to a very dark place where there would not be any AC power, and at that time inverters were rare and expensive.
Fortunately in the current era, nearly every car has a 120 AC power receptacle.
Furthermore, there are now a million different portable inverters that will plug into a vehicle's cigarette lighter (Politically Correct: 12V power port)
I'm not going to tether myself to a vehicle, because this little gadget right below will do the trick. It's a small inverter that uses the same batteries as my cordless hand tools. The other side has a tiny fan to cool the electronics, and it has a small flashlight on top. More than enough to run that clock drive motor.
In any event, here is the finished product of all that work - just waiting on the new travel case, finder-scope battery, and a clear night. It's been nothing but overcast and rain - and work - since I finished the refurbishment. Very much looking forward to mounting the old Canon Rebel Xti on it and seeing if I can grab a good image of M31!
Below: Messier 31 and 32 galaxies in Andromeda. You can see M31 in binoculars, but it won't look like this.
It will look more like this, which is why I wanted a big telescope in the first place!
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