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S Pisc is a red variable , spectra M5-M7 so it has an excess of red, as you've found.
The Yahoo StarAnalyser group under Robin L. is a tremendous forum for this type of spectroscopy.
Try some bright white/ yellow stars for comparison ie Vega, Alpha Cen etc.
My Rainbow optics grating (200lpm) failed and I return it. Ended up with a Baader 207lpm grating. Positioned about 60mm infront of the CCD ( I use the Canon 350, MX7c and AtiK16ic) gives good images.
Much much easier to use than a Littrow; you don't have to worry about guiding on a slit!!!
The SA, Rainbow and Baader are limited by the seeing conditions and star image size. The smaller the image the better, so large apertures and low focal lengths are ideal.
Spend the time with VSpec it will reward you well.
For a quick solar spectrum use the reflection from a needle at 20 meters or so as a reflection slit.
Last edited by Merlin66; 19-10-2008 at 12:10 AM.
Reason: typo
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