08-28-2016, 07:39 AM
Things like AWB are crude adjustments and don't really account for the transmission spectrum.
I did a low tech setup to measure the transmission characteristics of assorted filters before, to try to verify the performance of low cost IR filters and other astronomical use ones. I used an old torch so this would provide a wide emission spectrum well into the IR region. Shine it through a slit, through the filter, a diffraction grating and capture the resulting spectrum with a IR-cut removed camera. You can then feed this into inexpensive spectroscopy software which can then work out the amplitudes of the spectrum. Compare it to the case without filter, and you have a response. In my case I got a toy diffraction grating with no specification, not blazed. I had to work back with known narrowband sources to get the line spacing and thus an absolute wavelength scale. If they replace the low pressure sodium light outside my house with an LED one I'll lose my reference!
I did a low tech setup to measure the transmission characteristics of assorted filters before, to try to verify the performance of low cost IR filters and other astronomical use ones. I used an old torch so this would provide a wide emission spectrum well into the IR region. Shine it through a slit, through the filter, a diffraction grating and capture the resulting spectrum with a IR-cut removed camera. You can then feed this into inexpensive spectroscopy software which can then work out the amplitudes of the spectrum. Compare it to the case without filter, and you have a response. In my case I got a toy diffraction grating with no specification, not blazed. I had to work back with known narrowband sources to get the line spacing and thus an absolute wavelength scale. If they replace the low pressure sodium light outside my house with an LED one I'll lose my reference!
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.