Starlight Xpress Lodestar-C imager/guider - Manual (Page 8)

Lodestar C handbook Issue 1 May 2011
focal length guide ‘scope, as it offers somewhat finer RA guiding resolution in the X axis if this is
oriented East-West.
Guiding with the Starlight Xpress Lodestar software
With the Lodestar C connected to the PC and mount, open ‘Lodestar.exe’ and find the ‘Set program
defaults’ menu under the ‘File’ heading. If this is the first run of the software, you will get a warning
about the ‘ini file not found’, but ignore this and click on OK. You should now see a screen similar to
the one shown below:
The settings shown above are generally satisfactory as a starting point, although some will probably
need refinement for best results. In the example shown, the ‘autoguider socket’ on the Lodestar is
providing the control signals to the mount, but you might alternatively use the ‘LX200’ mode via the
serial port of the computer, if this is preferred. The Guiding Parameters are set to 6 pixels per second,
which corresponds to the typical drift rate of a 1000mm focal length guide telescope when the mount is
guiding at 0.5x sidereal speed. Longer focal lengths and/or higher guiding rates will require a larger
value to be set so as to avoid excessively fast corrections, which can cause erratic guiding or even
oscillation of the guiding errors to either side of the guide star.
Once the defaults have been set to values which you think will be approximately correct, save the
settings and open the ‘View’ menu. In this you will see an option called ‘Max palette stretch’. Open
this and check the ‘Activate stretch display’ check box. This will automatically boost the image
brightness so that faint guide stars can be easily seen – if necessary, you can adjust the slider for the
best results.
Now click on the camera icon to open the Lodestar control dialog, as below: