Orion STARSHOOT 52085 User Manual

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7. The ASCOM Telescope Chooser

(Figure 25) will appear. Select your
telescope model from the provided
choices. If your model does not
appear, it is not supported by the
ASCOM platform.

8. After you have selected your tele-

scope model, click the Properties
button.

9. In the window that pops-up,

choose your specific Scope Type
and desired Serial Port where the
computer will send commands to
the mount. Click OK when done.

10. Click OK in the ASCOM Telescope Chooser window.
11. In the Settings window, click the Close button.
Some telescope mounts, such as the Orion Atlas EQ-G and Sirius EQ-G, uti-
lize an “ST-4 compatible” autoguider jack. For easiest autoguiding with these
mounts, we recommend purchasing the optional USB Guide Port interface
(GPUSB). This adapter box will translate the autoguiding computer commands
from MaxIm DL Essentials into ST-4 pulse commands. The GPUSB connects
to the computer’s USB port instead of the COM port. A cable then connects
the GPUSB to the mount. In addition to installing the ASCOM platform on your
computer (from the Install ASCOM button in the Launcher), you will need
to install the GPUSB ASCOM driver (downloadable from the Orion website,
www.OrionTelescopes.com). Then, you can select the GPUSB in the ASCOM
Telescope Chooser.
Other telescope mounts accept commands in the “LX200 Protocol”. For these
mounts, it is not necessary to install the ASCOM platform to have the com-
puter “talk” to the mount. To setup the autoguider for mounts that use the
LX200 Protocol:
1. Connect the StarShoot Pro to your computer and open the Maxim DL

Essentials software.

2. In the Camera Control Window, click on the Guide tab.
3. Click on the Settings button.
4. In the window that pops-up, select LX200 Protocol for the Autoguider

Output Control Via. Select the COM Port of the computer you would like
to use to send commands to the telescope

5. Click the Apply button, then click the Close button.

autoguider Calibration

In order to properly control the mount, you must calibrate the system. The
exact orientation of the StarShoot Pro, the focal length of the guide telescope
optics, and the speed of the motor drive all affect the calibration. To perform
autoguider calibration:
1. Switch to the Guide tab.
2. Set the X and Y Aggr (aggressiveness) to 8 to start with. Set the Exposure

to 1.0 second. Under Guide Star, make sure the Watch box is checked.

Note: The X and Y Aggr (aggressiveness) controls on the Guide tab allows
you to adjust how vigorously star motions are tracked out in each axis. An
aggressiveness setting of 10 means that the StarShoot Pro attempts to track
out 100% of the motion, whereas a setting of 1 means that the StarShoot Pro
only tracks out 10% of the motion. Usually a setting of around 8 or 9 provides
the best tracking, since it reduces overshoot and helps ignore random motions
due to atmospheric seeing and wind loads. You should experiment to deter-
mine the best setting for your particular telescope.
3. Click the Settings button.
4. Maxim DL Essentials needs to know how fast the telescope moves in right

ascension (R.A.) and declination (Dec.) when the autoguider commands
are issued. To do this, the software will Calibrate the mount by moving it
back and forth on each axis. The Calibration Time determines how long it
activates the motors each time. The usual value is 5-10 seconds; start out
with a value of 5.

5. Make sure all of the Guider Enables boxes are checked.
6. For Autoguider Output, set Control Via and COM Port as required for

your telescope equipment. See “Computer to Mount Connection” if you
have not already done this.

7. Click Apply. You can leave this dialog box open, or Close it if you wish.
8. Make sure that the telescope mount is set to move at 1X sidereal or slower.

For some mounts, you must set the guide rate manually. The maximum
usable rate is 1X sidereal. If your mount does not drift quickly, then 0.1X is
recommended; otherwise use a value between 1X and 0.1X.

9. On the Guide tab, set to Expose, and click the Start button. A single

image will be taken. Ensure that a well-focused bright star (near the actual
object to be imaged) appears in the image. If not, adjust the guide scope
and try again. Make sure the star is roughly centered.

Note: The algorithm can be confused if another star appears in the frame; to
minimize this risk, calibrate on an isolated bright star.
10. Now, set to Calibrate, and click the Start button. A series of five expo-

sures will be taken; each time the telescope will be moved slightly. If the

Figure 25.

The ASCOM Telescope

Chooser provides an easy way
to establish a computer-to-mount
communications link if the mount is
supported by the ASCOM platform.