Equipment for Spectroscopy


DADOS Slit-Spectrograph with 200 L/mm and 900 L/mm gratings



The telescope mount, a Paramount ME from Software Bisque is secured onto a steel pier, which in turn is bolted to a concrete pad buried 6′ deep in the ground.

Telescope with calibrator

The telescope used for spectroscopy is the larger one above–a Takahashi Mewlon 250 with a 10″ aperture. The black device at the upper end of the telescope I call the Calibrator. Made from a plastic utility pail, it holds a gas discharge tube which can illuminate the spectrograph with a light source having clearly defined emission lines.

Spectrograph with Cameras

A DADOS Slit-Spectrograph at the base of the telescope has two cameras– one for capturing spectra and another for guiding. The main camera (larger red cylinder in the photo) is a ZWO ASI533 and the guide camera is a ZWO ASI120 Mini.


The outer side of the Calibrator has a power supply for the gas discharge tube.

The inner side of the Calibrator has a spring-loaded mount that secures the discharge tube.

Here is the illuminated tube (containing mercury vapor and argon gas) that faces the telescope.

The Calibrator stays in place during observations. The lamp can be turned on or off as needed. The calibrator blocks about 15% of the area of the telescope aperture, which hasn’t been a problem so far.