Meade LX850 User Manual - Page 21

Getting Started Fine Focus Knob Coarse Focus Knob Fig 31: Balancing the StarLock assembly Getting Started Focusing and Aligning the Viewfinder 1 . If you have not already done so, insert the Meade eyepiece into the diagonal mirror on the rear of the OTA. 2 . With the telescope properly balanced in both axes (See the section " BALANCING THE TELESCOPE" BEFORE performing this step), Unlock the RA and DEC clutches (Page 14, Fig. 10) so that the telescope moves freely on both axes. 3. Point the telescope at some well-defined and stationary land object at least 200 yards distant, such as the top of a telephone pole or street sign. Center the object in the telescope eyepiece (See Focusing the Telescope section below). Re-tighten the RA and DEC clutches. 4. With the object centered in the telescope eyepiece, look through the viewfinder and loosen or tighten, as appropriate, one or more of the viewfinder collimation screws (Page 7, Fig. 1, #2) until the viewfinder crosshairs are precisely centered on the object you previously centered in the telescope eyepiece. Twist the rear section near the eyecup clockwise or counter-clockwise to bring the object into clear focus. 5. Check this alignment on a celestial object, such as the Moon or a bright star, and make any necessary refinements. Fig 32: Dual speed Crayford focuser Focusing the Telescope Meade Advance Coma-Free (ACF): Note: All LX850 ACF optical tube assemblies ship from our factory with a Travel Screw. This screw MUST be removed before focusing the telescopes optics. For details see pages 3 and 10, fig. 6b. These optical tubes are equipped with an internal Crayford-style, zero image shift primary mirror focuser with dual speeds (7:1 ratio). The unique zero image shift design eliminates the need for a primary mirror lock and prevents image shift while focusing. To focus the telescope, turn the outside coarse focus knob in or out until the image is focused. For precise focus use the smaller fine focus knob for final focus. Meade APOs: The Meade APOs are equipped with a precision, aluminum-machined dual speed (10:1 ratio) Crayford-style focuser which eliminates image shift during focusing. Fine Focus Knob Fig 33: APO Crayford focuser Coarse Focus Knob To focus the telescope, turn the outside coarse focus knob in or out until the image is focused. For 21