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This is a composite photo of two frames, the first being a photo of Manchester, Washington, taken a few weeks ago; and the second, a shot of the moon snapped just last night.
I thought this would be fun ... an over-exposed shot of the moon to show the clouds in the sky. I'm not sure what star or planet is next to the moon, I didn't make note of it and too much time has passed now.
Yesterday I got my new Canon EF 70-200mm f/4L USM Telephoto Zoom Lens, and I just had to try it out. It's not the camera, you know ... it's the lens. OMG! What a lens! Here is the moon at a mere 200 mm, 1/600th of a second (Canon EOS 20D) ... it doesn't get much better than this. See ... I told you you don't have to have a fancy telescope to get some breathtaking images. :)
This photo of the moonrise over Seattle was taken at 5:45 a.m. April 3, 2008 from the Manchester Dock in Port Orchard, Washington, using a Canon EOS 20D DSLR camera. Photo by Jim W. Coleman.
HOLY COW! I put the level to the pier and it registered level. I figured I'd screw something up, you know, being an author and all, not one to get his hands dirty in concrete and better with words that conceptual engineering stuff ... but it came out LEVEL! This only means one thing ... if I can do it, you can. So far, my total cost of the pier is a LOT less than $100. This will be updated as I continue on to mating the telescope to the pier...as Tom Petty says ... the mating is the hardest part ... LOL!
The next challenge is designing and building an adapter system that will accomodate levelling and polar alignment corrections with a minimum of flexing and superb performance in vibration dampening. I'm considering steel, wood or aluminum. Once I make up my mind, I will design a custom solution and it will be included on this blog. Thoughts? Experience? Weigh in ... I'm sure a lot of people can benefit from your wisdom .. myself included. Thank you!
If all goes well, and you follow these VERY simple steps, you'll have a beautiful pier just like this one! I can't believe how easy it was, though it took half a day and several beers.
In several astronomy-related Yahoo groups I dabble in, the subject of rebar has come up over and over agian. Some insist on it, some don't. I think it's application-specific, though many of my esteemed online associates disagree. The pier is already encased in 3/4 inch polymer tubing ... the concrete is not going anywhere, it seems silly to me to reinforce it with rebar, especially if the concrete is mixed and poured correctly. But yes, I did throw in some rebar just to keep the pier-hippies happy.
I mentioned earlier that the most important part of all this is keeping it level. Here, I screw wood pieces into the floor to hold the pipe in place. Of course, if you're doing it RIGHT and building the pier first, you'll have to come up with a different method since there will be no floor (yet.) But it makes for a boring blog. This, I think, is unique. And works very well. :)
I can do this all day but if I forget to put in a picture of the concrete, I'll hear plenty back from those who want to see the concrete. Trust me, I've done this before. I mixed 13 bags of concrete, one bag at a time, in a wheelbarrow. Use 1 gallon plus 1.5 cups of water per 85 pounds of concrete. Mix well. Take a picture. Get a blog. It's that easy!
Perhaps most important of all is keeping your pier as level as possible. Of course, I'll be able to make levelling adjustments later at the plate level but the "more leveller" ... the better! Here is the bubble level I used to level my tripod-mounted wedge ... I'm using it here and it works like a charm!
Looking down into the empty sewer pipe as it is fixed in place, ready for rebar and concrete.
The 8 foot polymer sewer pipe is massive and hard to handle alone - but I did manage to get it upright and slide it into the hole. It was a tight fit and it knocked some crud down from around the rim, but I had dug deeply enough to make sure it would seat properly anyway. Wow, that sounded weird.
Reminds me of the old joke: I've been better legs on a piano bench. Anyway, here is yours truly cutting the notches out of the bottom of the pipe. A good Sawzall makes short work of it ...
Here is the hole, prepped and ready. Remember, it is a teardrop shape ... larger at the bottom than at the top. This will allow concrete to expand and form a heavy keel.
When deciding to build a permanent pier for my large telescope, I decided to just put on my engineering hat and figure out a way to do it ... without a lot of outside influence. I'm using a 14 inch sewer pipe (3/4 inch thick polymer, heavy!!!), filling it with concrete and going from there. As I dig the hole in a teardrop shape, I have to cut large notches in the bottom of the pipe so that concrete can freely flow from the pipe to the ground cavity.
Let me give you a tip. 13 bags of concrete handily fills an 8 foot pipe with barely any slop. But don't try to load them all into your new Saturn. I can't believe I saw someone trying such a feat. Make several trips. Or get a Dodge 2500 Cummins Turbo Diesel and THEN you can do it in one trip. :)
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