Hi everybody, tonight I tried a first attempt at spectroscopy
I had an old diffraction grating lying around (marked as 7500/inch) which I taped to the front of my Canon S5IS. I then mounted it on top of my scope with the tracking turned on, fully zoomed in, and successfully recorded the spectra of a couple of bright stars. Very exciting
There were immediately some obvious lines visible for both Sirius and Betelgeuse, so I loaded the raw shots into photoshop and cropped carefully around the spectra. I then resized vertically to 1 pixel to get the average value for each wavelength (I assume this will somewhat combat any noise in the image), and then I resized again to make the spectrum nice and broad.
I have attached the result as a comparison between the spectra of Sirius and Betelgeuse. It definitely shows something similar to what I would expect, but maybe some of you with more experience can tell me how much of this data is just noise? I suspect all the tiny lines are noise, but there is a lot going on especially in the Betegeuse spectrum which seems real enough to me. Are there perhaps reference spectra somewhere to compare with?
With regards,
Rolf