FOF - 01 September 2006... Sept 2, 2006 20:40:56 GMT -6
Post by Chicago Astronomer - Astro Joe on Sept 2, 2006 20:40:56 GMT -6
Far Out Friday Public Viewing Activities
01 September 2006
01 September 2006
This far out Friday session looked chancy...much cloud cover, but to the East there seemed to be clearing over the lake. We couldn't even accomplish any solar viewing with the amount of clouds to the west and overhead. So we brought out scopes of various types and allowed the public to view thru them. I left my favorite scope - the Nikon Refractor - in storage and decided to pick out a new telescope that we all discovered when we arrived.
Someone, sometime built this homemade 8" dob. Made from PVC pipe and plywood. It was a well thought out project and I wanted to see how it performed.
The scope has a nice clean mirror from Astronomics and a solid mirror cradle. The focuser is so-so, and the balance good. The only problem with it, and it's a big one, is that the altitude movement is jerky/stop and go. A good amount of force is needed to move it, and then it jumps too much. The rubbing surfaces stick and need work. Some smoothing and perhaps "milk Bottle" washers utilized for a smoother, free flowing movement. I took to banging it with my closed fist to get it to move in small increments.
The base is constructed from 1/2 plywood and is solid, and the OTA cradle is from 2x6 stock lumber...making it quite heavy. The PVC OTA tube is from PVC sewer grade pipe. Works quite well and no flex. The secondary mirror is of the semi-spiral type and also works well.
It was hard to find objects with the dob and lining up over the top of the tube was hit and miss. So I grabbed a 8x40 finder scope from the telescope storage area and crudely attached it on the OTA with electrical tape. It worked somewhat, getting me to the general area, but if we use this in the future, a more solid and permanent attachment must be used.
The optics were remarkably good and bright. Not as good as a refractor, but Jupiter, the Moon and M57 were good. It ran almost as good as the 10" SCT we had out. I just got very frustrated with the jerky movement of the alt.
The evening started out small and quiet, but as the night progressed, the skies cleared and we were presented with a semi-clear night, cool temps and large crowds. Several visitors brought their own personal telescopes for instructions on how to assemble and use them. We get a lot of beginner go-to scopes and owners who have no idea of the proper usage. I send them to Steve - who I think is the Go-To guru. He gets them on the right course.
We were even granted a visit by the ISS at 9:14 pm coming up from the WNW. Pretty bright and it disappeared in the Earths shadow before reaching zenith. The crowds were happy, and so were the Adler Telescope Operators.
From left to right: Arvind, Debra, Bill, Linda, Fred, Myself and Steve.
It was another good night for Chicago Astronomy and Adler FOF.
Chicago Astronomer Joe