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Plotting data

SPECPLOT will now plot your data (object spectrum, or object and sky) on the lexidata with sensible wavelength limits, with and without autoscaling. The wavelength calibration is via two ADAM variables, defining channel 0, and the wavelength interval per bin. Once the plot is complete, you can use the Lexidata cursor to mark features in the spectrum you might be interested in. The wavelength of the feature is written both to the Lexidata, and to the ADAM terminal. Use LEXPLOT if you want a hard copy on the line printer.

Useful procedures for quick FOS data reduction were written by Andy Lawrence and his team in May 1989, and are reproduced in Appendix D. In its most automated mode, a plot of a single object was produced in 1 min 58 secs from issuing the command to execute the procedure.

Again, it must be emphasised that there is no substitute for doing a rigorous reduction away from the telescope; the on-line reduction facilities are meant to enable the observer identify the spectrum with ease. To get the best from the data, use should be made of optimal extraction techniques (this is after all a Faint Object Spectrograph). Various reduction packages do already have such facilities.