Celestron NexStar 8i Telescope User Manual


 
19
D
D
i
i
r
r
e
e
c
c
t
t
i
i
o
o
n
n
B
B
u
u
t
t
t
t
o
o
n
n
s
s
The NexStar has four direction buttons (3) in the center of the hand control which control the telescope's motion
in altitude (up and down) and azimuth (left and right). The telescope can be controlled at nine different speed
rates.
R
R
a
a
t
t
e
e
B
B
u
u
t
t
t
t
o
o
n
n
Pressing the RATE key (11) allows you to instantly change the speed rate of the motors from high speed slew
rate to precise guiding rate or anywhere in between. Each rate corresponds to a number on the hand controller
key pad. The number 9 is the fastest rate (6º per second, depending on power source) and is used for slewing
between objects and locating alignment stars. The number 1 on the hand control is the slowest rate (1x sidereal)
and can be used for accurate centering of objects in the eyepiece and photographic guiding. To change the
speed rate of the motors:
Press the RATE key on the hand control. The LCD will display the current speed rate.
Press the number on the hand control that corresponds to the desired speed. The number will appear
in the upper-right corner of the LCD display to indicate that the rate has been changed.
The hand control has a "double button" feature that allows you to instantly speed up the motors without having to
choose a speed rate. To use this feature, simply press the arrow button that corresponds to the direction that
you want to move the telescope. While holding that button down, press the opposite directional button. This will
increase the slew rate to the maximum slew rate.
When pressing the Up and Down arrow buttons in the slower slew rates (6 and lower) the motors will move the
telescope in the opposite direction than the faster slew rates (7 thru 9). This is done so that an object will move
in the appropriate direction when looking into the eyepiece (i.e. pressing the Up arrow button will move the star
up in the field of view of the eyepiece). However, if any of the slower slew rates (rate 6 and below) are used to
center an object in the finderscope, you may need to press the opposite directional button to make the telescope
move in the correct direction.
1 = 1x (sidereal) 6 = 128x
2 = 2x 7 = 1.5º / sec
3 = 8x 8 = 3º / sec
4 = 16x 9 = 6º / sec
5 = 64x
S
S
e
e
t
t
u
u
p
p
P
P
r
r
o
o
c
c
e
e
d
d
u
u
r
r
e
e
s
s
The NexStar contains many user defined setup functions designed to give the user control over the telescope's
many advanced features. All of the setup and utility features can be accessed by pressing the MENU key and
scrolling through the options:
Tracking Mode This allows you to change the way the telescope tracks depending on the type of mount
being used to support the telescope. The NexStar has three different tracking modes:
Alt-Az
This is the default tracking rate and is used when the telescope is
placed on a flat surface or tripod without the use of an equatorial
wedge. The telescope must be aligned with two stars before it
can track in altazimuth (Alt-Az).
Nine available slew speeds