Specifications

AUTOSTAR CCD PHOTOMETRY 23
You will see the term “centroid” appear many times when reading
about CCD photometry. This is a bit of software “magic”. The
centroid of a star image is essentially its center of gravity or center
of brightness. The CCD software can find this center very
precisely. This is important, because when selecting the star for
processing, you do not need to select it exactly. Just as long as you
are close, the software will find the center (centroid) of the star and
reference everything about the star relative to that center. This is
also important when using the CCD camera for tracking, as the star
image center can be determined precisely.
4. In the pop-up window, select Set Reference Magnitude. (Fig.
3-7).
Figure 3-7. Select Set Reference Magnitude.
5. Set the Reference Magnitude for the Comparison star for that
filter and Click OK.. (Fig. 3-8.)
Figure 3-8. Set Reference Magnitude Window.