Spectroscopy
It seems that entry level spectroscopy can be enjoyed for relatively little cost. First steps have been taken using the Star Analyser 100 diffraction grating and the easy-to-use software RSpec.
The Star Analyser 100 grating is contained in a standard 1.25 inch threaded filter housing and attaches to the front of the imaging camera's nosepiece. It fits well with the GStar-Ex3 camera so as to display both the target star and its full first order spectrum comfortably within the camera's field of view. RSpec is a sophisticated application having many features that are well supported by a full range of tutorial videos. It accepts many forms of input - live video streaming from your camera; previously recorded video files; as well as individual images. Whichever input method is used the loaded spectrum is first displayed in graphical form calibrated by reference to the pixel count across its length. This is then re-calibrated into angstroms so as to identify spectral features by wavelength. The graph may then be re-configured into a standard form so as to allow for the inevitable falling-off of the imaging camera's response to light at shorter wavelengths. That re-configured graph can then be compared with a supplied library of star types so as to identify / confirm the spectral type of your imaged star. It will be interesting to see how far this low-level approach to spectroscopy can be taken. It has the potential for many interesting and satisfying sessions to come. |
Star and first order spectrum.
Crop from a single frame from a video of Mimosa (Beta Crucis). |