As common as the vintage C8s seem to be, they really don't pop up in my area at all, so when I saw this listed locally I snatched it up. The family I bought it from got it from their neighbors as they cleared out their attic for a move. They had no idea how to use it so they posted it for sale. They told me it had spent the last decade or more in their neighbor's attic, but before that it looks like it served as a somewhat serious astrophotography rig. I did my best to take my time and go over the OTA and mount as well as I could, but it's hard not to feel a little rushed when you're in a stranger's living room. The OTA had its share of scuff marks, the mount was pretty ugly, but the optics- despite having the usual haze on the corrector looked immaculate. There was no question, this was a hard working telescope at one point in its life (which, in hindsight, makes me think the optical performance I'd later find with it was no coincidence). At the time, I hadn't yet learned how to decipher the serial numbers, so when they told me it was a 1971, I accepted that as fact. I knew that the earlier C8's were more desirable, so that, coupled with the surprisingly nice optics convinced me to buy it. Everyone here will say I overpaid at $440, but I'm okay paying a premium gived the lack of local availability- especially as I prefer to get hands on with something this old before buying.
So as I said, whoever owned this C8 back when it was actively being used spent some time and energy customizing it to their needs. It sported an unusually heavy camera mount, a second finderscope- apparently taken from a C11 or C14, a telrad base, a threaded hole in the rear of the OTA that I can only guess was used to prevent mirror flop, among a couple other little things. The modifications were noteworthy for their ingenuity if not for their elegance. The base and fork arms had been painted a couple times. As I stripped them away I found a yellow base coat (maybe a primer?), a magnificent 1970's burnt orange/taupe, then the more recent flat brown. Functionally, the telescope was in reasonable working order though the Dec fine adjustment knob was not functional.
After giving the sellers a little tutorial on the telescope, and recommending some telescopes that would likely be a better, less frustrating fit for their ~8 year old son, I negotiated the purchase price, loaded up and brought my prize home. First order of business was to get the cobwebs out of the base, and give the whole thing a general wash down to get the decade+ work of attic off of it. I don't know what it is about old telescopes, but I could smell it across the room for a couple days. Thankfully, that eventually went away.
I debated whether to restore it for a couple weeks. The modifications didn't help its performance in any way since I wasn't imaging with a film camera, but they were all made during the telescope's original era. In the end, I decided that I would enjoy it more, and would be more proud of it if it looked a little fresher, so I decided to do some research on my restoration options. I cleaned the optics (more on those in a moment)- that was simple enough. They cleaned up beautifully. Then I took the big finderscope to the hardware store to see what I could do for paint matching. After 15 minutes of trial and error with no matches close enough for my satisfaction, I was beginning to lose hope. I thought I'd have to go to the German paint manufacturer mentioned in another restoration thread and dump $300 into a gallon of the Velvetone stuff. Just for kicks, the paint guy went over to check the spray paint isle. I was not optimistic at all considering we spent so long on the custom match options without any luck. I could not believe it, but he produced an almost IDENTICAL match right off the shelf. For anyone else considering a repaint, take a look at Rustoleum Satin Rustic Orange. I painted the big finderscope to try it out. I REALLY did not want to paint the C8 OTA unless I was certain I could do a good job with it. After letting it dry for a day, I sat it next to the OTA, and under a variety of light conditions, compared the two. It was astonishingly close. Rustoleum also has a pretty close match for the base as well that I used, although it's half a shade darker, but I was fine with that (it was the orange on the OTA I really cared about). I deliberated another couple days afraid I was going to screw up this ~50 year old telescope.
I eventually bit the bullet. I unbolted the camera mount, removed the OTA, masked everything off and got to work. Painting the OTA was a slow process. I held the can very far away as I desperately wanted to avoid a run. I laid down several of the thinnest coats possible to try to get the smoothest possible application. It took about 10 coats that way, but in the end, I think the result was worth it. I then painted the base and fork arms as well as the rear and forward ring of the OTA. Fortunately, the Dec fine adjustment knob was just a loose set screw. I put it all back together and the results are below! I'm really pleased with how it turned out, and I think the restoration was as respectful of the original configuration and paint scheme as possible.
So a couple interesting/unique aspects of this particular telescope. The optics are unlike anything I've ever seen in an SCT, and I think I now know why. The serial number put the date of manufacture in early 1973 (not '71). So I have to assume this is a Robert Goss production. I'm wondering if the original owner knew that, and that's why this particular OTA was chosen for his imaging. He definitely didn't care about the aesthetics of the telescope- it was apparent this OTA was selected for its optical performance.
The other unique aspect is the data plate- or plates. This is the last mystery I'm trying to work out, and if anyone can shed any light on this, I'd be eternally grateful. The base has a data plate with a serial number that puts its date of manufacture in the fourth quarter of 1973. But the OTA also has a data plate. The OTA's data plate is second quarter 1973. DOes anyone have any idea why that might be? My best guess is that the original base was defective and a new base was ordered. But the dataplate on the OTA looks factory original. There is no sign at all that it was previously removed from an old base and transferred to the OTA. After scouring the internet, I found another C8 OTA that also had a data plate on it. Are there any circumstances under which Celestron would have put a data plate directly on an OTA? Was this originally purchased as an OTA only? That would make sense if my hunch is correct that this astrophotographer was deliberately seeking an OTA with optimized optics. Does anyone have any thoughts on that?
Okay, enough yammering. Here are the before pics. Thanks for reading!