Quote:
Originally Posted by higginsdj
Lets not get carried away. Photometry with a web cam, although technically possible is subject to gross errors and will not be suitable for anything where precision photometry is required - ie exoplanets!
If one wants to do spectra well you can take on bright stars with a basic digital camera on a simple mount and a transmission grating. Or do the Moon or Planets or even the Sun with a CD or DVD as a reflection grating!
Vspec is free and is the quadi standard amoung amateurs. RSpec is great if you don't have any expectation that your students need to know much about spectroscopy - but it does cost money where VSpec is free.
Cheers
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Of course, you're not going to get accurate enough photometric precision from a webcam to be able to detect exoplanets (however, I've seen stranger things happen) but it can give reasonable results on most targets that you could detect, such as eclipsing binaries, variable stars etc. Any imaging device, even the most high spec CCD camera, can be subject to gross errors if not properly calibrated and used accordingly. Or if the conditions aren't conducive to photometry/spectroscopy.
Why not have groups in the class construct a simple spectrograph as part of their semester's work. One like this....
http://www.lpl.arizona.edu/~rhill/spect/spect.html
That's the reason why I suggested RSpec...makes it easier for the students to get into using spectroscopy without having them having to learn all the theory and maths behind it. Once they became comfortable with using the equipment and understood some of the theory, then you could introduce them to Vspec.
How simple would it be for some amateurs to get some good photometric shots of various stars for the kids to analyse. They could do a run on, say, GL876 over a number nights and have the kids look for planetary transits or starspots. Most amateurs are using their equipment just to take piccies. Nothing wrong with that but it would be enlightening for them to turn their hand to a bit of actual science every now and then. They may even like it
