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5.1.8 Star Search screen
After setting some guiding parameter (that You
want to use) an automatic star searching function
can be started from here. The guiding parameters
are the imaging parameters like analog gain and the
guiding exposure time. This two main parameters
are responsible for the limiting magnitude and the
precision of determining the star position. These values are typically constant for a well tested
system.
image gain
: (
decimal
, 2…9) profile
The analog gain value of the CCD’s signal. (See the table at 1.3.2)
expo.time
: (
decimal
, 50…4000 ms) profile
The exposure time for the star search and later for the guiding, in milliseconds. The
maximum is 4 seconds, there is no reason to increase this limit.
New search
: (
button
)
Starts a new star search with the given parameters. If the Camera is not working it is
started (taking some seconds) then the exposure time plus about 2.5 seconds for the
search procedure elapses. “Searching stars” text is displayed meanwhile.
Last results
: (
button
)
Shows the last search’s results again, goes to the search result screen, which appears
after each new search. Hold valid information until some other Camera function was
not used.
The search result screen appears after a star serach, which can be
seen at right.
The top left big rectangle shows the entire CCD area. Every active
point (pixel) on it represents a found star, these are the hits. At top right
is the index of the currently selected hit and the number of them. (The first 16 are memorized
and shown only.) To select the next or previous hit, press UP or DOWN buttons. The selected
one is displayed with a tiny rectangle (see on screenshot). The index orders the found stars
nearly by their brightness. The first index must be the brightest star found.
The brightness value (approximated) is shown below the big window. The unit is A/D
conversion unit and gives the sum of them for all the star’s pixels.
To start following the selected star press SET button (“See
→
”). Then You can monitor
the star on the Guiding screen (5.1.10) where this action jumps.
Note: the smaller rectangle is for live viewing of the selected star’s CCD part, currently
not used, always empty.
If the search was inefficient, this is shown. You can start a new
search with the same parameters by pressing the SET button (“New
search”) or go back to the Star Search screen by pressing ESC and
change the parameters.
