Orion 7817 instruction manual Alignment

9.Enter your current local time using the 24 hour clock format (example: 2:00PM = 14:00). Press ENTER to view the time you entered. If the time is incorrect, press ESC to go back to the previous screen. If the time is correct, press ENTER again.

10.If the date entered in step 8 falls between March and November, the hand controller will ask “DAYLIGHT SAVING?” on the LCD screen. Use the scroll buttons to select “YES” or “NO” to indicate if you are currently on Daylight Savings Time or not, and press ENTER.

11.The hand controller will now display “Begin Alignment?” Press 1 or ENTER to start the alignment procedure. Press 2 or ESC to skip the alignment and exit to the Main Menu.

You are now ready to begin the alignment procedure.

Alignment

In order for the GoTo hand controller to accurately locate and point to objects in the sky, it must first be aligned on known positions (stars). With the supplied information, the controller can replicate a model of the sky and the movements of astro- nomical objects.

There are three ways to align depending on your demand for accuracy. If you are using the GoTo controller for the first time, we recommend you begin with the three-star alignment. In most cases, a three-star alignment produces the most accu- rate alignment among the three methods. The description below will lead you through a step-by-step procedure on how to perform the three-star alignment.

Note: Before performing any of the alignment methods, be sure your finderscope is well aligned with the telescope tube.

Three-Star Alignment

1.From the alignment screen, select “3-Star Align” using the scroll buttons. Press ENTER to confirm your choice.

2.The hand controller will provide a list of stars available in your current sky for you to choose as the first alignment star. Choose a star you are familiar with using the scroll buttons. Press ENTER to confirm your choice. The mount will start slewing the telescope towards the chosen object. When the telescope stops slewing, adjust its position using the controller’s directional buttons until the chosen star is centered on the crosshairs of the finderscope. Now look in the eyepiece and adjust the position of the telescope (again using the directional buttons) so the chosen star is centered in the field of view of the eyepiece. Press ENTER to confirm the star is centered .

Note: The slewing speed can be adjusted by pressing the RATE button. Choose a desired rate between 0 (slowest) and 9 (fastest).

Note: The hand controller will make a “beep” sound once it has finished slewing to an object. Do not try to adjust the tele- scope before you hear the “beep” sound. The controller will only respond to the ESC button while slewing (which stops the slewing).

3.The controller will provide a list of stars that can be used as the second alignment star. Choose a star using the scroll buttons and press ENTER to confirm your choice. Repeat the centering procedure for the second alignment star using the directional buttons and press ENTER to confirm alignment.

4.The controller will once again provide a list of stars that can be used as the third alignment star. Choose a star using the scroll buttons and press ENTER to confirm your choice. Once again, repeat the centering procedure for the third alignment star and press ENTER to confirm alignment.

5.Once the three alignment stars have been entered and alignment is completed, the hand controller will display “Alignment Successful.” Press ENTER to access the Main Menu. Otherwise, “Alignment Failed” will be displayed, and the alignment procedure must be performed again. To do this, turn the mount’s power switch off, then on again.

Two-Star Alignment

Two-star alignment requires only two alignment stars but may produce lesser pointing accuracy than the three-star align- ment. The description below will lead you on a step-by-step procedure on how to perform the two-star alignment.

1.From the alignment screen, select “2-Star Align” using the scroll buttons. Press ENTER to confirm your choice.

2.The hand controller will provide a list of stars available in your current sky for you to choose as the first alignment star. Using the scroll buttons, choose a star you are familiar with and press ENTER to confirm your choice. The mount will start slewing the telescope towards the chosen star. When the telescope stops slewing, adjust its position with the controller’s directional buttons until the star is centered on the crosshairs of the finderscope. Now look in the eye- piece and adjust the position of the telescope (again using the directional buttons) so the chosen star is centered in the field of view of the eyepiece. Press ENTER to confirm the star is centered.

3.The controller will provide a list of stars that can be used as the second alignment star. Choose a star using the scroll buttons and press ENTER to confirm your choice. Repeat the centering procedure for the second alignment star and press ENTER to confirm alignment.

4.Once the two alignment stars have been entered and alignment is complete, the hand controller will display “Alignment Successful.” Press ENTER to access the Main Menu. Otherwise, “Alignment Failed” will be displayed, and the alignment procedure must be performed again. To do this, turn the mount’s power switch off, then on again.

One-Star Alignment

One-star alignment is the simplest and quickest alignment method, as only one alignment star is required. Due to minimal data input, however, a one-star alignment will not yield optimal results unless polar alignment is very accurate, and any cone error is minimized (see Appendix A). The description below will lead you on a step-by-step procedure on how to perform the one-star alignment.

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