Handbook for the SX remote control Spectrograph Issue 1, 17/8/20
The line wavelengths may now be calibrated by superimposing one of the RSpec reference spectra onto the display. Here is
the result of superimposing the ‘Nebula’ reference and then matching the strong emission lines by using the ‘Calibrate’ op-
tion in RSpec. You can see that the hydrogen and oxygen lines match up well with the calibration chart. The small ‘double
peak’ at the right is caused by sodium light pollution and is not in the calibration chart. You can see that the spectrum is
quite linear and matches the reference very well.
Bright nebulae, such as M42, give excellent calibration spectra, with very well defined emission lines. White or blue bright
stars, such as Vega, can also be used, as their spectra show strong hydrogen absorption features that are easy to identify. You
can, of course, also use the internal calibrator light source. This provides bright spectral lines from a mix of argon and neon,
