OK guys. Something to think about... I think.
Attached is a spectrum of Betelgeuse captured last night. It has been corrected for camera response based on the response curve generated from my Sirius Spectrum of the same night. Now if the camera response curve is accurate, shouldn't the corrected spectrum agree with the library spectrum?
The blue spectrum is my Betelgeuse corrected with the camera response from my Sirius spectrum. The green is the library spectrum for M2i (which is the nearest to Betelgeuse in the VSpec library).
Notice the library spectrum is low at low wavelengths, and high at high wavelengths. This suggests to me that the camera response curve is
not correct.
I've been thinking for a while that to get a true camera response curve would require averaging the response curves from the full range of star classes (O to M) so that the low signal to noise portions of the spectrum can be handled properly.
Thoughts?
Al.