Orion EQ-G instruction manual Setting the Slewing Speed

Power indicator light

12V DC

power jackPower switch

Autoguider modular jack

Hand controller serial jack

Figure 9-1.Atlas EQ-G mount faceplate.

Speed

buttons

Directional buttons

Set button

Figure 9-2.The Atlas EQ-G Dual-Axis hand controller

consult section 6 of this manual and attempt to polar align the mount more accurately.

Tracking can be deactivated or activated at any time the Atlas EQ-G mount is receiving power. In order to deactivate tracking, simply press and hold the Guide button then press the Slow button on the controller. Pressing the same button combination will reactivate tracking at the default (sidereal) rate.

There are three tracking rates used by the dual-axis control- ler:

Sidereal rate tracking is the default tracking rate for the Atlas EQ-G mount. Celestial objects are tracked using this rate which is equivalent to the rate of the Earth’s rotation.

Solar rate tracking is used to track the Sun over a long period of time. Solar rate tracking is activated by pressing and holding the Slow speed button, then the Right directional button.

Warning: Never look directly at the Sun through your tele- scope or its finder scope, even for an instant, without a professionally made solar filter that completely covers the front aperture of the instrument, or permanent eye dam- age could result.Young children should use this telescope only with adult supervision.

Lunar rate tracking is used to track the Moon at its rate of apparent motion across the sky. Lunar rate tracking is activat- ed by pressing and holding the Slow button, then the Down directional button.

Note: Solar and Lunar tracking rates can only be used when the Atlas EQ-G has tracking activated. If tracking is deacti­ vated, you must first activate tracking by holding the Guide button then pressing the Slow button.

Setting the Slewing Speed

In order to conveniently center an object in your telescope’s finderscope or eyepiece, you can set the speed rate at which the motors slew (move) the telescope when the directional buttons are pressed. The three speed buttons located near the top of the hand controller are used to set the slewing rates of the mount.

The slewing speed buttons each have two different speeds assigned to them. The slewing speed employed is dependent on whether or not the dual-axis controller has tracking activat- ed or deactivated (by holding the Guide button then pressing the Slow button).

With tracking activated, the Guide button will slew the Atlas EQ-G mount at a very slow speed equal to 1.5x sidereal rate. This speed rate will generally be used to guide a telescope while imaging with a camera. You can also change the Guide button speed rate to be slightly faster or slower (see “Setting the Guiding Speed”). If tracking is deactivated, pressing the Guide button will set the Atlas EQ-G to slew at 32x sidereal rate; this speed is too fast for guiding during imaging.

By pressing the Slow button with tracking activated, the Atlas EQ-G will slew at 4x sidereal rate. With tracking deactivated, pressing the Slow button will set the Atlas EQ-G mount to slew at 64x sidereal rate.

With tracking activated, the Fast button will set the Atlas EQ-G mount to slew at 8x sidereal rate. If tracking is not activated, pressing the Fast button will set the Atlas EQ-G to slew at 800x sidereal rate; this is a very fast speed that can be used to slew the mount from object to object across the sky.

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