My own personal human eye can see from about 425 or 450 nm in the short wave portion of the visible spectrum (blue or purple) to a wavelength of about 650 nano meters in the longwave part (red).
I have been experimenting around with my spectroscope which came in yesterday.
First, using a conventional fluorescent bulb I calibrated it for the bright green line at 546 nm which is the element mercury.
Then I started looking at various things and seeing the lines in their spectra. I got the pictures on the left from the instructions, and I took the top picture on the right while I had the spectroscope pointed at a cloud right next to the sun.
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The bottom picture on the right is what a compact fluorescent bulb looks like through the spectrascope. Here one can clearly see various individual emission lines lines, some bright and some dim.
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