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Tried to do some astrospectroscopy last night (fail), but figured I'd share the results anyway.
I taped a diffraction grating onto the lens flange (lens side, not camera side) to image some spectra- I was hoping to compare Jupiter, Spica, and Arcturus. For whatever reason, my old Sony worked much better for this- I think that Sony puts their sensor much closer to the lens flange than Nikon so the spectra still fall onto the chip. I ended up having to use a wide-angle lens to capture the spectrum, the trade-off being much less throughput. Images from my backyard- one of a streetlight (with Jupiter and Spica visible), and the other a neighbor's back porch light. These are 6s ISO 1000 exposures:
Unfortunately, the planet/starlight was just too faint for me to capture. The lights, however, have measurably different spectra (first one is the streetlight, most likely a Sodium lamp), the second an LED. Note also, the horizontal axis goes from red to blue and you can clearly see the Sodium lamp spectral peaks:
(for comparison: https://image.slidesharecdn.com/201...-all-you-need-to-know-7-638.jpg?cb=1358421058)
I taped a diffraction grating onto the lens flange (lens side, not camera side) to image some spectra- I was hoping to compare Jupiter, Spica, and Arcturus. For whatever reason, my old Sony worked much better for this- I think that Sony puts their sensor much closer to the lens flange than Nikon so the spectra still fall onto the chip. I ended up having to use a wide-angle lens to capture the spectrum, the trade-off being much less throughput. Images from my backyard- one of a streetlight (with Jupiter and Spica visible), and the other a neighbor's back porch light. These are 6s ISO 1000 exposures:
Unfortunately, the planet/starlight was just too faint for me to capture. The lights, however, have measurably different spectra (first one is the streetlight, most likely a Sodium lamp), the second an LED. Note also, the horizontal axis goes from red to blue and you can clearly see the Sodium lamp spectral peaks:
(for comparison: https://image.slidesharecdn.com/201...-all-you-need-to-know-7-638.jpg?cb=1358421058)