Celestar Manual
Using the Drive
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4.
Take a few minutes to practice guiding. This will help you familiarize yourself with the periodic error
of the drive and the operation of the hand control box.
5.
Press the “PEC” button once to activate the record (REC) mode. You will have 5 seconds before the
system starts to record. During this time the LED will blink once a second. When the duration of the
illumination changes to a half second, it indicates the record mode is active.
NOTE: The star should stay centered on the cross hairs for a few seconds without using the hand controller
before activating the PEC function.
6.
Guide for at least 5-1/2 minutes. After this time, the PEC playback function will automatically be
activated. To indicate the playback mode has started, the LED will change its blinking rate. It will
blink “on” for one second and “off” for a half second.
7.
Point the telescope at the object you want to photograph and you are ready to begin.
Note: If you press the PEC button while it is in playback mode, you will lose the previously recorded
information. Also, the fast slew functions are locked while the PEC functions is activated. This
eliminates the possibility of shifting the focus or moving the telescope suddenly during an exposure.
Hint: Ignore declination drift when programming the PEC.
Does the PEC function make unguided astrophotography possible? Yes and no. For solar (filtered), lunar,
and piggyback (up to 200mm), the answer is yes. However, even with PEC, off-axis guiding is still
mandatory for long exposure, deep sky astrophotography. The optional Reducer/Corrector lens reduces
exposure times making the task of guiding a little easier. More on each of these forms of astrophotography
in the section on “Celestial Photography”.
Connectors
On the drive base cover are three electrical connectors; two modular telephone jacks and one barrel
connector power source jack, tip positive. Starting from the left, the first, labeled “DEC “, is for the coiled
cable that connects to the standard DEC motor, and is appropriately labeled “DEC”. The DEC motor
allows you to make minor adjustments to the DEC axis using the buttons on the hand controller. Such an
accessory is mandatory for deep sky astrophotography.
Next outlet, labeled “HCU”, accepts the male end of the hand controller unit. The hand controller is NOT
needed for normal tracking. It is used to make corrections during long duration astrophotography or to
center objects in the field of view. To plug the hand controller into the drive base:
1.
Hold the end of the hand cable with the modular phone jack over the outlet in the base.
2.
Orient the jack so that the plastic tab is down.
3.
Slide the jack into the outlet until it clicks
The hand controller is now installed and ready to use. Pressing the buttons on the hand controller will
speed the motor up or slow it down allowing you to make corrections for long exposure astrophotography.
There are two speeds available for the users. For details of the hand controller operation, see the next
section.
The last outlet labeled “12V DC,” is for an external power source, which will accept either the optional AC
adapter or the supplied car battery adapter. The connector on the telescope is “tip positive”.
