Has anyone noticed that Anders REFUSES to answer as to why he has lied across numerous websites in regards to health issues, place of residence and type of residence in order to push an ANTI CFL, pro incan agenda?
On to the reply ....
For one, quoting a supplier website who is trying to market their product is not scientifically sound.
For two, quoting a supplier that quotes a scientific paper that has been proven WRONG is really not good at all.
They quote a paper written in 1996: "In a 1996 paper entitled, "The Reengineering of Lighting Photometry," Dr. Sam Berman sets forth a new theory on the workings of the human eye where the function of the rods and cones are not mutually exclusive as previously believed. To prove his theory that rod receptors were at work all the time, Dr. Berman measured pupil diameters which were exposed to light sources of equal total output but with different spectral power distributions. The sources which emitted more energy closer to 508nm and away from the peak cone sensitivity of 550nm resulted in smaller pupil sizes proving his theory that not only were rod receptors at work at all times, but also that the rods controlled pupil size and not the cones as previously thought."
This paper was proven to be WRONG rendering the assumed conclusions WRONG as well. Neither rods nor cones are responsible for pupil dilation. It has been shown that a 3rd sensor in the eye controls pupil dilation and perceived brightness. It has also been shown the rods saturate at much beyond about 20 lux.
Then there is there not completely founded conclusion about light levels being a primary driver of color perception which is not accurate (not the headlight conclusion). The primary driver of changes in color perception is the spectrum of light that the eye has been adjusted too. You will note in their study they say "However, it was noted that museum light levels are much lower than standard light indoor light levels." GUESS WHAT AT THAT POINT MUSEUM LIGHTING WAS? ... low color temp incandescent (no UV). Essentially what they showed is that under likely 2700K incandescent, that 3500K (or so) is perceived as "WHITE". That is not surprising at all.
What that does not mean is that the eye perceives 3500K black body as white. In fact experiments have shown that at 300lux, within an order or magnitude of almost all interior lighting, that 3500K black body is still perceived below the black body if used as the only lighting source.
Nice table you quoted for what the color temperature of "SUNLIGHT" is. Did you notice that the one they identified as DAYLIGHT was 5000-6500. Designing a light source to match sunrise and sunset, a small portion of the day, is not a great goal.
Let's address some other things ... "Because these variations are caused by refractive diffusion, their spectrums are still equivalent to a black body curve"
For one, sun reaching the earth only approximates a black body ... it is not "equivalent", it is just close.
For two, sunlight is not reddish at sunrise and sunset because of "refractive diffusion", it is because of wavelength specific scattering (rayleigh scattering approximation / rayleigh extinction) .. the same reason the sky is blue. It most definitely DOES NOT behave as an equivalent CCT black body radiator. Not sure where Solux has that "supposed" 3500K daylight curve ... since a) daylight is consider 5000K+, and two, this does not look much like spectrums I have seen of sunrise/sunset.
Should we address Solux "Mixing" a 3000 and 4700K source and then claiming that this showed 3500K to be best? If you mix two light sources on the black body you do not get another source on the blackbody. In this case, you will get a light source under the blackbody ... which is actually where you need to be in order to be perceived as white.
Anders, no doubt you will blindly reply to this post to get the last word, but as opposed to MISLEADING CPF members with the illusion of knowledge, perhaps some research (maybe a course or two) would be in order before blindly quoting sources without understanding the underlying information okay?
Semiman
On to the reply ....
For one, quoting a supplier website who is trying to market their product is not scientifically sound.
For two, quoting a supplier that quotes a scientific paper that has been proven WRONG is really not good at all.
They quote a paper written in 1996: "In a 1996 paper entitled, "The Reengineering of Lighting Photometry," Dr. Sam Berman sets forth a new theory on the workings of the human eye where the function of the rods and cones are not mutually exclusive as previously believed. To prove his theory that rod receptors were at work all the time, Dr. Berman measured pupil diameters which were exposed to light sources of equal total output but with different spectral power distributions. The sources which emitted more energy closer to 508nm and away from the peak cone sensitivity of 550nm resulted in smaller pupil sizes proving his theory that not only were rod receptors at work at all times, but also that the rods controlled pupil size and not the cones as previously thought."
This paper was proven to be WRONG rendering the assumed conclusions WRONG as well. Neither rods nor cones are responsible for pupil dilation. It has been shown that a 3rd sensor in the eye controls pupil dilation and perceived brightness. It has also been shown the rods saturate at much beyond about 20 lux.
Then there is there not completely founded conclusion about light levels being a primary driver of color perception which is not accurate (not the headlight conclusion). The primary driver of changes in color perception is the spectrum of light that the eye has been adjusted too. You will note in their study they say "However, it was noted that museum light levels are much lower than standard light indoor light levels." GUESS WHAT AT THAT POINT MUSEUM LIGHTING WAS? ... low color temp incandescent (no UV). Essentially what they showed is that under likely 2700K incandescent, that 3500K (or so) is perceived as "WHITE". That is not surprising at all.
What that does not mean is that the eye perceives 3500K black body as white. In fact experiments have shown that at 300lux, within an order or magnitude of almost all interior lighting, that 3500K black body is still perceived below the black body if used as the only lighting source.
Nice table you quoted for what the color temperature of "SUNLIGHT" is. Did you notice that the one they identified as DAYLIGHT was 5000-6500. Designing a light source to match sunrise and sunset, a small portion of the day, is not a great goal.
Let's address some other things ... "Because these variations are caused by refractive diffusion, their spectrums are still equivalent to a black body curve"
For one, sun reaching the earth only approximates a black body ... it is not "equivalent", it is just close.
For two, sunlight is not reddish at sunrise and sunset because of "refractive diffusion", it is because of wavelength specific scattering (rayleigh scattering approximation / rayleigh extinction) .. the same reason the sky is blue. It most definitely DOES NOT behave as an equivalent CCT black body radiator. Not sure where Solux has that "supposed" 3500K daylight curve ... since a) daylight is consider 5000K+, and two, this does not look much like spectrums I have seen of sunrise/sunset.
Should we address Solux "Mixing" a 3000 and 4700K source and then claiming that this showed 3500K to be best? If you mix two light sources on the black body you do not get another source on the blackbody. In this case, you will get a light source under the blackbody ... which is actually where you need to be in order to be perceived as white.
Anders, no doubt you will blindly reply to this post to get the last word, but as opposed to MISLEADING CPF members with the illusion of knowledge, perhaps some research (maybe a course or two) would be in order before blindly quoting sources without understanding the underlying information okay?
Semiman
Color temperature is perceived differently depending on light levels. At lower levels, 3500 is perceived as daylight color.
https://www.solux.net/cgi-bin/tlistore/infopages/eyes-response.html
Here you can see the frequency spectrum graph of SoLux superimposed on the spectrum of natural daylight at 3500K.
http://www.photoanswers.co.uk/News/...atural-daylight-halogen-lamp-available-in-UK/
The color temperature of natural daylight is quite variable depending on time of day and conditions:
3000-4000 K Sunrise/Sunset (clear sky) 5000-6500 K Daylight with Clear Sky (sun overhead) 6500-8000 K Moderately Overcast Sky 9000-10000K Shade or Heavily Overcast Sky
Because these variations are caused by refractive diffusion, their spectrums are still equivalent to a black body curve. In fact, I suspect this may be how the special coatings in SoLux work. If you look at the graph the spectrum is completely smooth. I do not think they would be able to achieve this by conventional colored filters. Rather than transmitted light, SoLux relies on reflected light from the special coating inside. Apparently the leftover undesired portion of the spectrum is transmitted through the coating, where it is absorbed by black paint. The coating may operate on the same principle that makes eye color blue (in some people).