JMI Telescopes MAX Computer - Manual (Page 11)

Page 11
The timer is started by pressing the ENTER button, which
will temporarily cause the display to show the following:
START
The elapsed time from the moment you pressed the ENTER
button will then be displayed until you press ENTER to stop
the timer or MODE to exit the timer mode.
ENCODER
This mode is primarily used for verifying proper operation of
the encoders. The encoder angles (in whole degrees)
relative to their startup positions is shown. For equatorial
mounts, the first axis is Right Ascension and the second
Declination; for Alt/Az mounts, the first axis is Azimuth, the
second Altitude.
For more information on using this mode to test the
performance of your encoders, see the Encoder Test
section beginning on page 4.
POLAR
(NGC-miniMAX and NGC-MAX)
Although the MAX computer can be used without it, having
your telescope polar aligned is desirable in many cases.
The accuracy of a clock drive depends upon this alignment
for visual and especially photographic purposes. The
POLAR mode is used to achieve a highly accurate polar
alignment.
Before using this mode, you must change your setup to
reflect either an EP (Equatorial - Polar aligned), or GP
(German - Polar aligned) mount. See SETUP, below, for
help on doing this. If you do not do so, upon attempting to
enter this mode nothing will happen or you will see:
ONLY FOR EP GP
Once you have ENTERed the
POLAR ALIGN mode, use
the UP and DOWN buttons to choose a reference star by
name from the list of 30 to 40. The star you choose should
be between 60º and 120º from the pole — with those near
the celestial equator being best. Do not press any more
buttons yet.
With your mount at least roughly on the pole (the closer you
are to begin with, the faster the process), point the
telescope at your chosen star and press ENTER once it is
in the center of your eyepiece. A bright asterisk (*) may
momentarily appear, followed by a display similar to the
following:
POLARIS 77 ← 83 ↓
This indicates the direction and distance to Polaris. You
should now move your telescope to the indicated position
just like under GUIDE mode. When you have zeroed both
angles, your display should look like this:
POLARIS 0 ♦ 0 0 ♦ 0
If your mount is polar aligned, Polaris will appear near the
center of a moderately powered eyepiece. (Don't worry
about the offset of Polaris from the actual pole — the MAX
computer is accounting for this.*) If Polaris is not near the
center of your eyepiece, you will need to adjust the altitude
and azimuth adjustments of your mount until Polaris is
centered in your eyepiece. Be sure not to move your
telescope relative to your mount — the computer's display
should remain as shown above. If you should accidentally
move the telescope itself, you can zero the angles again so
that the display does match that above.
Now press the ENTER button, and you will briefly see a
reminder to adjust your altitude and azimuth, then a display
similar to this:
SIGHT PROCYON
You should now point your telescope back at your reference
star and center it in the eyepiece. Press ENTER and you
will be instructed to guide back to Polaris. Repeat the
above process from this point as many times as desired.
With each iteration of the process, your telescope's polar
alignment should become more and more accurate. Two or
three iterations should be sufficient for most visual work,
while up to five or six iterations may be required for long-
exposure photographic work.
Users installing a mount permanently will find this procedure
helpful for obtaining an accurate polar alignment, however
one of the more time-consuming methods (star drift or
photographic) should be used for fine tuning.
* While your telescope's optical tube is being aligned on
Polaris, the mount's polar axis is actually being aligned on
the pole, not Polaris.
SETUP or INSTALL
This mode is used to tell the MAX computer some
characteristics of your mount. The meaning of each of the
setup parameters is defined here. The first display,
showing the selected mount type, will be similar to the
following:
SCOPE EQ
Mount. This setting informs the MAX computer of the
type of mount your telescope is on. The six types to choose
from are AZ, AV, EQ, EP, GQ, and GP (the NGC-