This is a binocular guide to the Moon, developed by CAAS, to assist in the identification of features on our only natural satellite.
By Jim Dixon
I’ve been seeing these 12″ MDF rounds at my local hardware store and knowing that I was just going to have to make something out of them. Originally I planned to use two for the altitude bearings of a Dobsonian scope but when I purchased an SCT instead I decided that one would be perfect for the top of a heavy-duty tripod.
Modeled after those from Celestron, my tripod has turned out very well if I do say so myself. Besides the MDF round, I used pine 1x2s (Oak was twice as expensive and I used a lot, besides pine worked fine), several lengths of aluminum, some strips of galvanized steel, a bit of 1/4″ plywood, hinges, and assorted bolts, screws, and nuts.
- I cut the 1×2 to 36″ lengths and glued two together three times to make the central piece of each leg. Then I used a router to cut a groove down on side of each and glued strips of steel to give me a pressure plate so that I could lock the adjustable legs. Thumbscrews are used to lock the legs in place.
- I sandwiched the central pieces between the two outer 1x2s with index cards as spacers and then started building the aluminum brackets that hold the pieces together. I was able to use a hacksaw to score the aluminum so that it would bend at the corners properly. Besides adding a lot of strength, these aluminum brackets added a lot to the appearance.
- The photo shows the rest of the key components: The ¼”x 2″ boards that make us the leg braces, hinges, screws, and bolts. The photo doesn’t show the rubber pads on each leg.
- After using the tripod for a couple of months to make sure I was done, I stained and sealed the legs.
- There is one more enhancement I’m going to make which is to add a triangular accessory shelf that will fit between the legs.
Not counting any tools I had to purchase, I was able to build this for about $75, which is less than a third of the cost of a name brand tripod. Although I tweaked it over several weekends, I had a functional tripod after the first weekend.
By Jim Dixon
When I first heard about these “quick focus” devices, I had no idea of their size and thought they were knobs that replaced the normal focusing knobs. After all, a larger knob would allow you finer control over focusing. When I realized they were aperture masks, I thought “yeah”. These sell for $47 or more depending on your telescope’s size although admittedly they double as a lens cap.
I wasn’t willing to spend that $50 on something that I had my doubts about. I purchased a sheet of foam core board from a hobby shop for $4 and made one that, to my amazement, actually works. The three holes form three images when the telescope is out of focus. As you close in on focus, they merge. As you can see from the picture, it doesn’t have to be very well made either.
One night I was trying to observe Sirius B, the much fainter white dwarf companion to Sirius. The difficulty in this is the closeness of the pair and the 9 or 10-magnitude difference. I heard about using a hexagonal mask to redirect the light from the bright into six spikes rather than one bright circle. I used some of the same foam core board left over from the focusing mask. It really does work. Light from the bright companion is channeled down the spikes allowing you to see objects closer to the bright companion.