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SPECTRUM/SPECPLOT - On-line data reduction

SPECTRUM is a program to perform quick on-line data reduction. You just have to follow the instructions. It obtains a 1-D spectrum from an area that you select with the cursor, subtracts from it the chosen sky and stores it in a T(emporary) file that you can plot. SPECPLOT Tn gives a plot with the wavelength scale and a cursor.

SPECTRUM lets you delimit the object area with the Lexidata cursor. You have various options when selecting the sky area. You can chose not to define a sky area, a sky area which does not include the object area or a sky area which includes the object area. For this last choice (which takes the longest to execute), the sky under the object is interpolated by fitting a quadratic function to the sky on either side.

Notes

If, to improve the signal-to-noise ratio, you are using the sum of more than one RUN, SPECPLOT will produce a normal PLOT, without the wavelength scale. This is because, at present, the image manipulation routines do not propagate al the necessary headers to the output file. SPECPLOT labels the wavelength scale based on the given central wavelength and a linear dispersion scale.