Gemini-2 and Gemini-1 Telescope Mount Controller
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Interactive Hand-Controller Menus - click on green button to Navigate
This is the Safety Limit setting screen. It is also described on the

Note: Safety Limits may not take effect until you power down and back up. This has been my experience.  The writer of the code says they take effect when set.

The limits can be set either using the Web interface, on the Mount Selection Page, (it is under Menu-->Mount-->Limits) or on the menu to the left.

Note that the Web limits are set for left and right side, while the hand controller uses East and West.  If using the hand controller, follow these steps. (The hand controller method only works correctly on August 16 or later firmware.) Also the safety limits are referenced to the CCW startup position. If you did not start up with a Cold start, or Warm Start with the mount at CCW, you must do this before setting the limits. It a very bad idea to start up with a "Warm Restart" and assume that the Gemini 2 has remembered the CCW. You can tell the Gemini-2 to part at CCW to make sure it knows where CCW is.
  1. Turn off tracking by placing the mount into Terrestrial mode.  Menu->Track->Terrestrial
  2. Move the RA using the Left-Right buttons to the Eastern Limit.  NOTE: ALWAYS START WITH THE EAST LIMIT. Loosen the clutch in Dec. Make sure you can spin the telescope in Dec without it hitting the mount.  Use the Menu->Mount->Limits->"Set Limits Here" button, to set the Eastern Limit. 
  1. Move the RA using the Left-Right buttons to the Western Limit.  Loosen the clutch in Dec. Make sure you can spin the telescope in Dec without it hitting the mount.  Use the Menu->Mount->Limits->"Set Limits Here" button, to set the Western Limit. You now have set the Limits
  2. The Western Goto Limit determines how far pass the meridian that the Gemini-2 will do a flip.  It is calculated like this. Note that the Meridian is at 90 degrees.
    The point of Meridian Flip = Western Safety Limit - Western Goto Limit.
    An example is if you have the Western Safety limit set to 100 degrees - The Western GoTo limit of 2.5 degrees (default) you end up with a point of flip of 97.5 degrees, or 7.5 degrees past the meridian. Any target selected that is past this will do a meridian flip.  Any target on the East side (Northern Hemisphere) will not do a meridian flip.
  3. The rear RA tactical buttons are active so that you can move the mount while in this screen.  They were made active with the Sept 20, 2013 hand controller firmware update.  Move to where you want to set the limit and press "Set Limit Here"

Also the Limits are are stored permanently as "physical step" values and they don't depend on the model. But: the Safety limits depend on a good CWD position of the RA axis. With a sync or model, the Index parameters are set instead. Nevertheless, with a Western limit of 95 degrees set and a 2.5 degrees GOTO limit, there are only 2,5 degrees left. Especially if pointing at the Zenith, there will be an unreachable zone if the model has to take care of a rough polar alignment.
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