Last updated: 15 July 2000

Adjusting the DEC Setting Circle

From: Andrea Perfetti (a.perfetti@dpssrl.com)

Using the following procedure and polar aligning the ETX I'm able to put the desired object in the FOV of the eyepiece at 7.7mm! First of all put the instrument on a flat surface and, using a little bubble level on the center of the base level it perfectly.

DEC Setting Circle

Now move the OTA upward without moving the base and put the bubble level on the center of the front lens cover.

DEC Setting Circle

Carefully level the OTA with the base of the ETX, tighten the declination knob and loose the circles: rotate them till you read 90 then retighten them.

DEC Setting Circle

When observing an object, remember to reset the RA circle before moving to the next: say you are observing Vega at 18h36m this is also the value you read on the RA circle. After 5 minutes of observing, the circle will read 18h36m + 5m: 18h41m. If now you want to go observing Deneb which is 20h41m you must first reset the circle to the value of Vega 18h36m or you wil be offset by +5 min: 20h46m which is not what you want.

Go back to the Tech Tips page.

Go back to the ETX Home Page.

Copyright ©2000 Michael L. Weasner / etx@me.com
Submittal Copyright © 2000 by the Submitter
URL = http://www.weasner.com/etx/techtips/dec_circle.html