Handbook for
cycle has completed, the optimum correction speeds, backlash correction and hysteresis values will have been calculated and inserted into the default boxes. Note that the pixels per second rate for the R.A. correction will vary with the cosine of the declination angle, so you may need to alter this value, or
Exposure times and image calibration
S.T.A.R. 2000 will enable you to greatly extend the exposure times of astronomical images and so detect much fainter objects. The limiting factor is set largely by the increasing effect of light pollution on these extended exposures, but dark sky sites will permit 30 minutes, or more, to be used. You will also begin to see signs of amplifier luminescence at the upper
The software includes an option to generate properly matched dark frames, by recording the number of guiding downloads executed during the taking of the image and using this to add the correct amount of amplifier glow to the resulting dark frame. To use this option, you must record the dark frame immediately after the ‘light frame’, or the download count will be lost. Simply cover the ‘scope aperture, select ‘Take matching dark frame’ in the self guider part of the camera control interface and press ‘Take Photo’. Application of the ‘Gradient fi lter’ (under the Filter Menu) can be used as a final ‘tweak’, if necessary.
Flat field frames can be taken in the usual way, and are not affected by the use of S.T.A.R. 2000.
A clip from a
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Using the add-on autoguider:
An alternative to STAR2000 and a very useful accessory is the
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