Of course Chris, streetlights often use Mercury vapour, so are you sure you didn't measure the spectra of the hundreds of lights in Sydney Harbour, and not the two or three on this aircraft?
The camera used, a Nikon 5000, only has a 3x optical zoom, so the tele converter (how was that attached as the Coolpix doesn't have a bayonet mount, does it?) could ony have made this 6x, meaning lots of other light sources were in the frame. Was the object tracked, or a a fixed picture taken, with the object streaked? Why no inclusion of the picture in the .pdf?
How did you calculate the wavelength of the light from the image captured, I'm having a hard time seeing how you could make sense of the information. When I've used diffraction gratings to measure spectra, it's been from a single point source, passed through a diffraction grating, projected onto a screen, and measured there. Multiple sources, some moving and some static relative to each other passing through a diffraction grating, then through camera optics, and then being captured, seems like a bit of a feat. Care to tell us how you separated your sources, and managed to measure the spectra? And please show us the image you worked on.
