Photo / CCD
Besides using the Visual / Photo / CCD Star Spectroscope visually, you can use the grating cell to photograph spectra through a telescope or with telephoto lenses. Also, CCD cameras can be used, as described in the Fall 1995 CCD Astronomy and the June 1999 Sky & Telescope, page 14. A photographic spectroscope is often called a spectrograph. 

Nebula-Seeking Filter
The grating cell of the Visual / Photo / CCD Star Spectroscope can be used as a planetary nebula-seeking filter. Some small planetaries are star-like and can be difficult to distinguish from the stars in a field-of-view. When the grating cell is screwed into a 1.25" eyepiece or hand-held above the eyepiece, it transforms stars into continuous, streak-like spectra while any small planetary nebula becomes conspicuous because it remains a point of light. A similar technique is described in the "Webb Society Deep-Sky Observer's Handbook, Volume 2, Planetary and Gaseous Nebulae".

Filter Testing 
Sky & Telescope magazine featured nebula filter tests in the July 1995 issue. You can perform similar tests on any nebula filters and color filters you may own. First, set up your spectroscope on a bright A-type main-sequence star like Vega or Sirius. These stars have strong H-Beta lines right at the bandpass of nebula filters. Then simply hold the filter to be tested between your eye and the spectroscope. You will instantly get a vivid demonstration of how nebula (light pollution) filters work. At a star party it should be possible to compare quite a few filter types and brands.

Public Stargazing
If you have ever conducted a public stargazing session, you know that when discussing the properties of stars, someone inevitably asks, "How do they know that?" Now, instead of being limited to replying, "Astronomers use special instruments attached to their telescopes", you can actually demonstrate one of those instruments! Children especially enjoy the vivid colors seen through both spectroscopes.

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