The two fluorescent wraparound lights you showed at 2:02 and 2:17 have magnetic ballasts in them! You can tell because of the banding on the video, caused by the very slight difference between the refresh rate of the camera and the flicker frequency of the fluorescent lamps. High-frequency electronic ballasts do not cause the banding because they drive the lamps at tens of thousands of hertz, unlike the 60 Hz of old school magnetic ballasts, and this frequency is so fast that the phosphor does not have a chance to glow down in between pulses, making it appear as perfectly steady light even to cameras. Additionally, you can tell that the lamps in the fixtures use halophosphate phosphors, as the bands are yellow. Dark green or black bands would indicate deluxe halophosphate phosphors, bright green would indicate tri-phosphors, and yellow and green bands would indicate a blend of halophosphate and tri-phosphors. Halophosphate phosphors are the old-school type, they use two calcium halophosphate materials that emit orange-yellow and blue light, and varying the proportions of these components changes the color temperature. Because they emit mainly yellow and blue light, they do not cover the light spectrum very well, and the CRI of these lamps is relatively poor (only 62 for cool white halophosphate fluorescents). Deluxe halophosphate phosphors add an additional red component on top of the standard halophosphate coating, which boosts the CRI to around 88. However, these lamps are only around 75% as bright as the standard halophosphate lamps. Tri-phosphors use red, green, and blue phosphors to produce white light, similar to how a TV uses red, green, and blue pixels. Since your eyes are most sensitive to red, green, and blue light, these lamps are very efficient and have a very good CRI, around 85 for pure tri-phosphor lamps. Again, varying the proportions of the three components can produce various color temperatures. Sometimes, tri-phosphors are mixed with halophosphates to create “in-between” lamps that have a CRI of around 75.
Wow, you have an amazing eye and attention to detail! This video it was hard to capture the lights because of the glare through the camera (smartphone), impressive you can still see so much! Thanks for sharing!
The two fluorescent wraparound lights you showed at 2:02 and 2:17 have magnetic ballasts in them! You can tell because of the banding on the video, caused by the very slight difference between the refresh rate of the camera and the flicker frequency of the fluorescent lamps. High-frequency electronic ballasts do not cause the banding because they drive the lamps at tens of thousands of hertz, unlike the 60 Hz of old school magnetic ballasts, and this frequency is so fast that the phosphor does not have a chance to glow down in between pulses, making it appear as perfectly steady light even to cameras.
Additionally, you can tell that the lamps in the fixtures use halophosphate phosphors, as the bands are yellow. Dark green or black bands would indicate deluxe halophosphate phosphors, bright green would indicate tri-phosphors, and yellow and green bands would indicate a blend of halophosphate and tri-phosphors. Halophosphate phosphors are the old-school type, they use two calcium halophosphate materials that emit orange-yellow and blue light, and varying the proportions of these components changes the color temperature. Because they emit mainly yellow and blue light, they do not cover the light spectrum very well, and the CRI of these lamps is relatively poor (only 62 for cool white halophosphate fluorescents). Deluxe halophosphate phosphors add an additional red component on top of the standard halophosphate coating, which boosts the CRI to around 88. However, these lamps are only around 75% as bright as the standard halophosphate lamps. Tri-phosphors use red, green, and blue phosphors to produce white light, similar to how a TV uses red, green, and blue pixels. Since your eyes are most sensitive to red, green, and blue light, these lamps are very efficient and have a very good CRI, around 85 for pure tri-phosphor lamps. Again, varying the proportions of the three components can produce various color temperatures. Sometimes, tri-phosphors are mixed with halophosphates to create “in-between” lamps that have a CRI of around 75.
Wow, you have an amazing eye and attention to detail! This video it was hard to capture the lights because of the glare through the camera (smartphone), impressive you can still see so much! Thanks for sharing!
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