AP900 upgrade question
Posted 04 January 2013 - 01:44 PM
I'm planning to buy an AP900 QMD. Is it possible to upgrade from QMD to GTO?
Posted 04 January 2013 - 03:29 PM
Posted 05 January 2013 - 01:51 AM
here is my AP600QMD conversion
i was planning to buy a 900QMD (they go below $4K) and convert it to GoTo as well... but the thing is the old QMD mounts don't have the quality of the new GTO mounts. My QMD has quite a bit of declination stiction which makes guiding not trouble-free.
also for comparison.. my AP600E QMD has a periodic error of around 11" peak-to-peak, and according to some folks on the AP-UG yahoo group, some old AP900 QMDs had PE in the 30" range, albeit smooth.
by comparison, the Mach1 I ended up getting has 2.5" of periodic error. And that's before periodic error correction.
so the new GTO mounts are really much more than just a GoTo version of the QMD mounts. They have numerous mechanical improvements that aren't immediately obvious.
Posted 05 January 2013 - 02:10 AM
Bad news. I'll check the Astro-physics page. Thanks!
If you're a visual observer, these QMDs are a solid mount that can be picked up for less than half the GOTO versions sell for. My 1200 is about 20 years old, yet any tech help is a phone call away.
Posted 05 January 2013 - 07:32 AM
Further - I realized that if visual is all you want, converting to GoTo is not the best option. It would be better to just buy an Argo Navis for the mount. I did try a JMI computer, and didn't like the experience. But Argo Navis is the best. And in retrospect, I should have gone for it.
Posted 05 January 2013 - 08:58 PM
Posted 05 January 2013 - 11:38 PM