Unfortunately, equatorial platforms are latitude-specific. They are simulating having the telescope move across the sky as though they were turning in a circle around Polaris. As I said, somewhat magical
Besides the latitude-specific nature of the equatorial platforms, they have several other deficiencies. They typically only track for about an hour, at which point you unlock one clamp and rotate it back along its magical pseudo-polar axis. This is not a big deal for visual use, especially for public astronomy.
For astrophotography, there are two problems. That reset will make your 4 hour exposure of M51 completely useless. Also, the nature of how this simulates an equatorial mount causes rotation of the image on the eyepiece.
The obvious solution to latitude is to raise the south end of the platform by seven degrees to compensate. In this case, 21.5" (distance between front and rear of the platform times sin (7 degrees). This gives a 2.62" lift. This does not sound so bad. It scares me thst it might be unstable to move the center of gravity that far to the side.
Alternative strategies:
1. Sell the existing platform (a lovely all-aluminum platform made by the late Gregg Blandin) to someone in my latitude and buy the more sophisticated platform made by Tom O.
2. Remove the OTA from its cradle, and attach it to a dovetail plate that goes on a high payload equatorial mount. This is very expensive, mostly because high-payload mounts are very expensive. This is also slightly more uncertain as to how to make it work.
3. Rebuild the telescope in a carbon fiber tube which should get it below 50 pounds. High expense carbon fiber tubes 20" ID are not cheap), a lot of work, and uncertain results.
Simpler, less obvious solution. Shim the south end of platform 2.62". Bolt ground board to platform. Bolt platform to the board with casters. Even if center of gravity is a little off, it should not make it a leaning Tower of Pisa.
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