Re: Mach2 with TEC180 for visual
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Nice collection of scopes and mount.
Having a strong steel pier is of course the ultimate for stability. The ATS portable piers are probably the most solid piers you can get next to steel or concrete. I have one in our Hawaii observatory and will be installing a second one shortly.
From: Jeff B <mnebula946@...>
Sent: Mon, Oct 11, 2021 6:12 pm
Subject: Re: [ap-gto] Mach2 with TEC180 for visual
For a bit of perspective, I have had several AP mount and refractor combinations that have worked just fine for visual use. By "fine" I mean the ability to easily and accurately focus at high power without a lot of juggling in the image (interestingly, a small bit of slow back and forth in the image actually seems to make accurate focusing easier for me at times).
My Mach 1 with a Losmandy HD tripod was "good" with my old AP 178 F9, which is rather light weight for its aperture but a long moment arm.
My AP1100 with the HD tripod was a "very good" support for the 178 F9 but "ok to good" with the TEC 200ED (F9, and about 63 pounds fully configured with dovetail, aft ring with 60mm F8 finder, counterpoise weight system and bino-viewers)
My AP900 was VG to excellent supporting 178 F9 and G to VG with the 200ED (actually, I was very impressed at how well it handled the scope). But this was with the AP900 installed on a fabricated steel pier, filled with sand and bolted to a concrete pad.
My AP1200 is just flat out excellent with the TEC 200ED. Sure, if I bump it hard enough it will go through a couple of highly damped cycles, but its system "Q" factor is of such high quality, there is NO vibration when focusing even up to 500X. And honestly, it is the most satisfying visual scope/mount system I have ever used. It too is bolted down with the steel pier.
Our County Parks Department's observatory has a 220 F12 achromat riding on another AP1200 (again bolted to a sand filled steel pier). The OTA with all accessories and bino-viewer, tips the scales at 80 pounds and is a solid VG to E.
Now my experience has also been that for portable setups, the tripod and its coupling to the ground is at least as important as the mount itself when it comes to vibration.
I have attached some pictures of some of these examples.