Ken_stargazer replied to Ken_stargazer's topic in Discussions - MountsCosmic Geoff, Thank You. I find it noticeably steadier. With the tripod, there was some "wobble" from either flex of the tripod's legs themselves or else of the rubber tips of the legs, but that's gone (and there is also no longer any need for vibration pads). Also, there is no longer any risk of accidentally bumping into a tripod leg which was my biggest headache. I was initially concerned about flex of the upper (longer, second) pipe, but I that's why I chose 1-1/2" i.d. (it's about 2" o.d.) galvanized steel pipe, because there would be virtually no flex at the very modest lengths, 3-1/2 to 4 ft, we're dealing with -- I can slap it sideways using my hand without any noticeable reaction. Of course, the lower (first) pipe (1 ft long) that is solidly embedded in concrete in the ground is also not an issue. The NPT threads of the assembly would allow some wobble if the pieces aren't joined tightly, but I torque it slightly with a pipe wrench when I screw it in -- just remember to use antiseize so you can release it.
Ken_stargazer started following Solid but removable Scope mount, without tripod legs
Ken_stargazer posted a topic in Discussions - MountsIn the dark, I kept tripping on my NexStar 8SE's tripod legs; I also wanted a consistent position on my driveway to set up my telescope at night. So I built a mount on my front driveway with the best view (albeit surrounded by tall trees) of the sky, but removable for cars to pass and tolerate snow blowing when necessary. [Above] I started having a hole drilled (by a professional contractor) into my concrete driveway. A 1-1/2” (i.d.) galvanized steel pipe with a brass, threaded coupling (to prevent corrosion) was embedded in concrete (that was covered by a sealant) in the hole. The depth of the top of the coupling allows a removable, square-headed, screw cap to close it to the elements (along with antiseize on the threads), and it all remains slightly below the grade of the cement driveway allowing me to run over it with my snowthrower blade without catching. I used threaded pipe, instead of just a pipe sliding in as a “sleeve”, to eliminate any chance of a “wobble” when the second, upright pipe is attached. [Above] This is an inverted view of the Celestron NexStar 8SE’s tripod’s mounting platform (essentially, the tripod without its legs). The threaded socket into which the tripod’s center rod (to support the “lens caddy”) is metric threaded: 12x1.75 mm. Unable to find an inexpensive eyebolt of that size, I found a “Rod End Bolt”, along with suitable nuts. I also placed a couple of washers in place to ensure that the rod will remain centered in the second galvanized pipe. [Above] I sat the platform on top of a threaded flange for a second, longer pipe (length is your preference for the telescope's height), to ensure that the platform will be level (the first and second pipe are “plumb”). I drilled a hole for a 7/16” transverse bolt through that second pipe that will also pass through the Rod End Bolt’s hole that is inserted inside the pipe. A little trial-and-error adjustment and final tightening of the Rod End Bolt into the underside of the platform ensured that the whole assembly was snug and without “wobble”. [Above] Now the whole assembly (second pipe + mounted platform) can now be screwed into the first threaded pipe’s brass coupling in the driveway. It is now ready to support the 8SE and even the weight of a wedge, without any wobble. The red, straight line painted on the driveway is a North-South line (determined by a shadow at Local Solar Noon) to help with the telescope’s nightly set-up. Now it takes barely a minute to screw out the plug and screw in this mount. It's rock solid and steady, and its position is consistent every night. More, when not using my telescope it's not an obstacle to cars or to my snowblower. Thanks for looking.
Ken_stargazer posted a topic in Getting Started Equipment Help and AdviceHello. I'm a new user of my telescope, a Celestron NexStar 8SE, and unfamiliar with the effects of accessories. So I'm asking this in order to best select a set of eyepieces (my telescope came with only one 1.25", 25mm eyepiece). My first question involves a Reducer/Corrector: I've heard of the benefits of using Celestron's accessory, a 0.7X "Reducer/Corrector (#94175) to brighten dim objects (f10 to f6.3). However, I also understand that it widens the field of view, so I'm wondering how it would affect apparent magnification. For example, if I like the view of a hypothetical object (i.e, how much it fills the field) using a 15mm eyepiece, how might that change when I use this Reducer/Corrector? Would I then, using the Reducer, want to use a shorter focal length eyepiece (e.g., a 10 or 12 mm) instead. My second question involves going to 2" eyepieces (this telescope came with a 1.25" eyepiece), noting that if I do go to 2" eyepieces, I'll also include buying a fully 2" diagonal as well rather than an adapter to a 1.25" diagonal. I have been led to believe that 2" eyepieces have a wider field of view, so I wonder how that compares to the 1.25" eyepieces. For example, hypothetically assuming that I want to retain a certain magnification that I get from my 1.25" diameter/25mm f.l. eyepiece, am I right to believe that I would want to go to a shorter focal length in a 2" eyepiece? I really appreciate any help and advice you can offer. Thank You, in advance.