Quote:
Originally Posted by Poita
So if I took a picture through solar film with a colour camera, and checked the RGB values, then the image would lean towards the green?
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No.
White light from the sun, has a certain shape across the spectrum. It is not a flat line across all the frequencies. The peak intensity of white light is in the green part of the spectrum. For red stars, the peak intensity is near the red end, for blue it is near the blue end. So, following Wien's Law, as I say, all white stars, have their peak intensity in the green part of the spectrum and are therefore
technically green.
Some "white light" solar filters have a colour cast about them. That is, they don't block the same proportion of photons at all frequencies across the spectrum, the closer they are to flat linear (same proportion of photons blocked at all frequencies) the closer the image of the sun will appear to white.
Cameras, you must keep in mind, are manufactured to replicate what we see. So a colour photo through the white light solar filter,
shouldn't look any different to what you would see, but often of course it does to varying extents depending on how well the manufacturer has built the camera to replicate what you would expect to see, and how you have various settings, such as colour/white balance, set, etc.
Am I explaining myself any better?
So a peak intensity at green does not mean we see green. If the shape of the spectrum matches the sun, it will appear white. If the peak is steeper than the sun it will appear green. If the peak is flatter than the sun's spectrum, it will appear pink (Pink = white - green
).
Even mono cameras often have peak sensitivity around the green part of the spectrum. This provides a mono image which is appealing to the eye, and this means we have to correct for the "instrument response" to do valid scientific measurements in spectroscopy.
Clear as mud?
Al.