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I liked the idea of the moveable strings used as rays!
Got this recommended to me as well, great video.
This is worth watching. It is a clear and precise explanation. I might include it in my photography classes because he describes it so succinctly.
Loved it. For a guy like me who has struggled to understand how that little picture box I hold actually works… This was great.
Now, I know at a small diameter aperture you can increase the exposure time to collect the right amount of light… But when it comes to light entering the camera and affecting the sensor, what does the adjustable exposure value do?
If your lens has a 62mm diameter ( so about 30cm²) there is an area in the subject that send all its photons to the sensor cell in focus. If you are wide open any photon in the cone between the subject and the 30cm2² front lens are funneled to the sensor cell. If you use a smaller aperture, only the photons that hits the 15cm² area around the center of the lens will end up in the cell which will therefore see half the photons.
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After adjusting the exposure time the only other variable you have left is the amplification of the signal the sensor(or negative) captures. This can be done analogically(electrically or chemically) or after the camera converts the signal to digital, which at the end of the day, is no different than boosting it in post production or in your darkroom while printing your negative.
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Finally, a practical application of string theory! 
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Someone who got his job by pulling the right strings…
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When it comes to light entering the camera and affecting the sensor, I prefer to think in terms of exposure (lux-seconds).
A formula for sensor exposure is:
Hm=0.65 x L x t/(F^2) where:
Hm=average sensor exposure (lx.s)
0.65=a constant to do with average lens characteristics
L=source luminance (cd/(m^2))
t=exposure time (s)
F=aperture setting (focal length/aperture diameter)
and t/(F^2) is your “adjustable exposure value”.
As to the shutter and aperture, it can be seen from the formula that exposure is directly proportional to the exposure time and inversely proportional to the F-number squared, all other things being equal.
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