The "Synchronize" function is especially important after a "Warm Restart," because it 

must be executed in order to enable the other submenus of "Align Telescope." 

5.3.1.5  Polar Al. Assist 

The "Polar Al. Assist" menu item does not appear after a "Cold Start" until you have 

executed   Synchronize.    It is used to roughly polar align your mount by slewing back 

and forth between 2 stars and adjusting the mount' s elevation and azimuth at each star.  A 

complete description of how to use this function can be found in Chapter 3, section 

3.4.2.3 of this manual. 

5.3.1.6  Polar Axis Corr. 

Similarly, the "Polar Axis Corr." menu item does not appear until a pointing model is 

established by performing at least one "Additional Align."  This function (polar axis 

correction) allows you to polar align your mount with fairly high accuracy by taking 

advantage of the pointing model that Gemini is building.  A detailed description of how 

to use this function can be found in Chapter 3, section 3.4.2.3 of this manual. 

5.3.2  Object Database 

Messier 

NGC 

IC 

Sh2 

Solar System 

Bright Stars 

SAO 

WDS 

GPN 

LDN 

LBN 

User Defined* 

5.3.2.1  Database Use 

Gemini 

s "Object Database" contains 11 predefined catalogs and 1 user defined catalog.  

Objects from these catalogs are accessed by executing "Object Database

" 

and then either scrolling to the desired object from the selected catalog, or "typing in" 

(scrolling each digit to) the object 

s catalog number.  When the object is then selected by 

pressing the RA+ button, Gemini confirms the object 

s identifier (name) or catalog 

designation, and displays the hour angle of the object in minutes, and its elevation in 

degrees.  

There is an important difference between the catalogs that enumerate their objects using a 

catalog number (such as Messier or NGC) and those that identify their objects by 

coordinates (such as GPN and WDS).  In the case of the former, simply entering the 

catalog number will select the object.  In the case of the latter, after you enter a number of 

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