A little side story

Mostly a repost, but with some corrections and clarifications. 

Growing up during the Mercury and Gemini programs, I also got interested in telescopes and astronomy.  Something that was talked about everywhere was making your own telescope, including grinding the mirror.  The most commonly talked about telescope was a 6" f8 reflector, which you would grind the mirror for and make an equatorial mount out of galvanized plumbing parts.  I had never really started down that road, but by 7th grade, I had my first good telescope (a 4" f10 reflector).  Note in both cases, the f number is the focal length divided by the objective's (mirror's) diameter

In junior high, maybe the end of 9th grade, I learned there was one of those "every 20 years" closest Mars oppositions coming (August 1971 - right before the start of my high school senior year) and a friend and I decided we were going to make our own telescopes to see Mars.  We had books that said a great first scope to make was an 8" f7. So about two years before the close opposition, this friend and I bought 8" Pyrex mirror blanks, the "plain glass tools" that we'd need, abrasives and the empty 55 gallon drums we'd need to do the grinding on.  I was going to do it! 

Except without someone to guide you through the rough points, it's not necessarily easy.  In my case, I banged the mirror on my work stand (the 55 gallon drum, which my parents graciously allowed in my bedroom) and took a big chip out of it.  Instead of finishing the mirror and painting the chip flat black, the accepted wisdom of how to fix such things (which I didn't know), I tried to grind the chip out and, well, never got that 8" mirror made. 

While I didn't get mine finished, my friend did.  I don't even remember seeing Mars during that opposition. We were still friends, so something tells me, maybe his wasn't all that successful either.  Since it was over 50 years ago, and we lost touch with each other within a couple of years of graduating high school I can't ask but I suspect his may not have worked well, either. 

Fast forward 20 years to about 1990, now an adult working for Major SE Defense Contractor, I got the bug again.  This time, it was the information age and the internet offered a precursor to the web called Newsgroups.  Buoyed on by the folks on sci.astro.amateur, and with the help of a really great book, I made my first successful mirror and first good telescope, a 6" f8 mirror; that is, 48" focal length, and a Newtonian Reflector.  It makes a good size, but like a lot of addictions, it leaves you wanting more.  

I started a bigger mirror, 10" f6.  I missed the focal length; it came out f5.6 which is still perfectly usable.  This was a more difficult mirror, but a 10" mirror gives a serious advantage over the smaller mirror.  Area goes up as radius squared, so it has a little under 3 times the area as the 6" mirror.  I completed the 10", again with some help from people I met on the newsgroups.  I built the telescope as a Dobsonian, altitude-azimuth style mount.  This is actually the second iteration of the telescope, when I replaced the typical cardboard tube (used as a form when pouring concrete) with a metal tube. 

By extreme luck, I completed this telescope in early 1994, the year that Comet Shoemaker-Levy 9 crashed into Jupiter.  Nobody in all of human history had ever seen such a thing, and we saw the impact marks on Jupiter from our backyard through this telescope.  Armed with star charts and the old fashioned method of "star hopping" (going from landmark star to star in your finder scope until you find the object you're looking for), I spent several years exploring the sky with it.  

The story goes a bit sideways here.  These telescopes have a lot going for them but they have a serious drawback: they don't track an object so that you constantly have to reposition the scope while looking at a planet or other object to compensate for the apparent motion in the eyepiece.  On higher powers, say 300x or more, the earth's rotation can cause a planet to drift cross the field of view in seconds. (As a side note, this is half the speed of a clock's hour hand.  A star on the celestial equator goes from due east to due west in 12 hours.  That's the same as going from 3 to 9 on a clock - which shows that the clock does it twice as fast). 

It's now in the early 2000s, and my career had gotten to the point where I had "more money than time" and with that the funds to buy a commercial telescope with a computerized tracking mount and a new feature called "GoTo".  With a GoTo system, you typically tell a handheld controller what object you want to view and it moves the telescope until it puts that object in your field of view.  I literally saw more deep sky objects in my first night with that scope than I used to see in a season without the GoTo feature. 

One night, we set up a test in the backyard.  We put the commercial telescope, an 11" compound reflector side by side with my 10" reflector.  We pushed the same magnification on both scopes.  Both Mrs. Graybeard and I thought the image in my telescope was sharper - more detail visible. 

This led to a plan to go back to using mine and getting a mount for it that allowed tracking and GoTo.   Much to my surprise, I don't have any pictures of the telescope at that time.  I repainted it blue because the original paint job chipped maddeningly (I bought the tube pre-painted inside and out).  Not to get into too many details but some old plastic parts had broken down with age and had to be replaced.

The big telescope tube is 12" diameter and 60" long, for scale. Oh, for closure, look to the right of the black mount and you'll see an odd-shaped blue structure with a white disk on its side. That's my 6" f8 reflector that I started the story with. It's in a square, plywood tube, but it's a Dobsonian style mount, too. (The black box with the orange strap on a cart is an electrically heated smoker.)
I connected the controller computer to the mount and turned it on. It acted like I'd turned it off the minute before. Never missed a beat. There's still a little bit of maintenance to do on things but it's usable. The thing is, I haven't used it since the year was in single digits, like '08 or '09. Our neighborhood trees (including my own) have grown up so much that it's difficult to see the sky, and what we can see is light polluted. To use it now, the 4" casters won't cut it. Those are fine for the porch, but to get it out to where it can see even a sliver of sky, I need 20 or 26" mountain bike tires on the mount. Or garden cart wheels. And that's another redesign and building project. 

As a general rule, around here the best time for observing, at least as far as weather, bugs and general comfort matter is winter. As a coincidence, the better weather reduces radio noise from electrical storms, so winter is better for all my hobbies, even including working in the machine shop. Some backyard astronomy info might find its way into the space coverage.