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Miaplacidus,
A couple of hundred dollar will get you started with a Star Analyser grating (SA100)...Think of it as "Spectroscopy 101"
Darrell,
Unfortunately your situation isn't to uncommon. The SA100 usually comes with a DVD which explains the basics of setting it up and getting that first spectral image.
You really need to gain an understanding of what the grating is and what it does before letting it loose on a telescope.
The distance between the grating and the CCD chip should be around 50-60mm - this depends on the pixel size of the camera and the width of the chip.
The grating is a lo res "slitless" spectroscope - this means that the resolution (and height...) of the spectrum is controlled by the size of the star image. Seeing usually limits this to about 2-3 sec arc.
The basics:
-Around an f5 system is ideal.
-Align the grating so that the "lines" are parallel to the side of the chip. This should give you a spectrum horizontally across the CCD.
-Look at the first image you get...there should be a bright star image (zero order image) and a spectra on either side. One is much brighter than the other - that's the one you want to record.
-Position the zero order star close to the edge of the field and the brighter spectrum across the middle.
-Start with an A class star - the Hydrogen lines are much easier to see (and will help you with the calibration later)
initially focus on the star - but as soon as you have the framing correct - ignore the star image (!) and concentrate on the spectrum. Refocus to show the absorption bands and bring them into the best contrast you can.
If you can get this far you're about 10% there!!!
The rest, we can discuss, comes down to the background removal, wavelength calibration and instrument response correction.....
At this stage we can then seriously look at the spectrum and do some basic analysis.
Onwards and Upwards.
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