Instruments Telescopes Instruction Manual RCX400
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Looking at or near the Sun will cause irreversible damage to your eye. Do not point this telescope at or near the
Sun. Do not look through the telescope as it is moving.
How to Drift Align Max (Northern Hemisphere)
Important Note:
You will need a reticle to perform this procedure
1. Center your reticle on a bright star near the Eastern horizon.
2. Look through the reticle while pressing Autostar's right and left Arrow keys.
This will slew the mount back and forth in the R.A. axis.
3.
Loosen and rotate the reticle until one of the crosshairs matches the right-left
path of the star as you press the Arrow keys. This crosshair is now on the R.A.
axis. The other axis is therefore on the Dec. axis. Carefully secure the reticle in
place (do not move the crosshairs).
4. Observe the bright star you have chosen. If, over time, it drifts off the R.A. axis,
use the latitude adjustment knob to bring it back
past center. Experience will
teach you how much to move the alt knob. If the star drifts slowly, use only a
small amount of correction; if it moves quickly, use a much larger amount of
correction.
5.
Use Autostar's up and down keys to bring the star back to center. Perform step
4 repeatedly until it does not drift on the Dec axis for a few minutes.
6. Next, center on a bright, Southern star. This star should be within 10° to 20° of
the celestial equator.
7. If the star drifts above the RA axis, use the Azimuth adjustment knob to move
the star to the right and down until the star is almost out of the field of view. If it
drifts below the R.A. axis, use the Azimuth adjustment knob to move the star to
the left and up.
8. Use Autostar arrow keys to center the star again. Repeat steps 7 and 8 until
the star no longer drifts off the R.A. axis for a few minutes.
9. Go back and check the first star and see if it is drifting again. And then recheck
the second star also. Keep repeating steps 4, 7 and 8, until there is no more
drift in either of the stars you have chosen for a few minutes.
Your telescope is now drift aligned. Next, collimate your telescope.
Collimation
This collimation procedure is for Meade RCX models only. The optical collimation
(alignment) of any astronomical telescope used for serious purposes is important, but
in the case of the RCX design, such collimation is absolutely essential for good per-
formance. Take special care to read and understand this section well so that your tel-
escope will give you the best optical performance.
As part of final optical testing, every Meade
RCX400 telescope is precisely collimat-
ed at the Meade factory before shipment. However, vibrations in shipping can cause
the optical system to become misaligned.
Re-aligning the optics is
, however, a
straightforward process with the RCX400.
Test your Collimation
Before collimating an RCX400 model, you will need to test your collimation.
To test the collimation, center a bright star that is overhead, or use a “hot spot” of
reflected Sunlight from a chrome car bumper, with the supplied 24mm eyepiece. Allow
the telescope to adjust to the temperature of your observation site before proceeding;
temperature differences between the optics and the outside air can cause distortion
in the images. Autostar II offers two options in the Utilities menus that take tempera-
ture readings: “OTA Temperature” (the temperature of the corrector plate) and
“Ambient Temperature” (the temperature of the air around the fork arms).
When the star or hot spot is centered, de-focus the image. You will notice that the out
of focus star image looks like a ring of light surrounding a dark central spot; the dark
central spot is in fact the shadow of the secondary mirror. You may notice multiple
rings; these are called diffraction rings. Focus until the diffraction rings fills about 10%
of the e
y
epiece field-diameter. If the dark central spot is offset in (i.e., not concentric
with) the diffraction rings, your telescope’s optical system is misaligned and requires
collimation.
Note:
See:
http://www.astrocruise.com
/polarnew.htm
for a website dedicated to
drift alignment of Meade
telescopes. Site offers
extensive tips from an
experienced drift align
specialist.