2008-06-19; 13:18 (solar altitude 61.6)
direct sun
with baseline at 293nm set at zero
Spectrum 437: SUN Edit
DeleteMeasurement
Brand |
other other |
---|---|
Lamp Product |
Sun Direct sunlight |
Lamp ID |
SUN (01/2000) |
Spectrometer | USB2000+ |
Ballast | - no ballast or default/unknown ballast - |
Reflector | |
Distance | 0 cm |
Age | 0 hours |
Originator (measurement) | Frances Baines |
Colorimetry
Colorimetry is the science to describe physically the human color perception. The wavelength range 380 nm - 780 nm is visible to humans and detected by three different photoreceptors. Many Reptiles see the range 350 nm - 800 nm and have an additional UV photoreceptor in their retina.
WARNING: The measurement range (350 - 800 nm) is not sufficient for this evaluation! Data is only available in the range 290.19 - 750.27 nm. Results are shown anyway but should be ignored by anyone except experts.
Whereas a spectrometer measures the intensity in every tiny wavelength interval resulting in thousands of individual intensities, the human eye only measures three intensities detected by the three cones. The same is true for the reptile eye with usually three or four photoreceptors. Effectively the detailled spectrum displayed above reduces to a much compacter bar graph displayed below. The photoreceptor sensitivites from these L-Cone, M-Cone, S-Cone, and U-Cone are used, they are chosen as an average of measured reptile photoreceptor sensitivity curves. The bar graph also shows as reference the intensity seen by the three or four photoreceptors for average sunlight (id 1).
From these three numbers the colour coordinate and the correlated colour temperature for humans are calculated using the CIE standard method. I adapted this concept to a "3 cone reptile (M,S,U)" and a "4 cone reptile (L,M,S,U)". I am sure, that this adaption to other colour spaces makes sense mathematically and this is also done in scientific research regarding colour vision of animals, however I have not seen calculation of colour temperatures for other animals in the scientific literature. Even if it is hypothetical, at least this shows, how arbitrary the colour temperature is, and that the colour temperature calculated for humans does not apply to reptiles. The colour spaces also show the colour coordinates of different phases of daylight ((ids 1, 338 – 451, 511 – 513 ), indicated by crosses, coloured in the appriximate colour perceived by a human.
Human (CIE) | 3 cone reptile | 4 cone reptile | |
---|---|---|---|
Cone Excitation | |||
Colour Coordinate | ( 0.31 ; 0.32 ) | ( 0.4 ; 0.39 ) | ( 0.26 ; 0.3 ; 0.29 ) |
CCT | 6600 Kelvin | 4900 Kelvin | 5500 Kelvin |
distance | 0.046 | 0.047 | |
colour space | 3-D-graph not implemented yet |
Vitamin D3 Analysis
Vitamin D3 is produced by UVB radiation around 300 nm. 7DHC/ProD3 present in the skin is converted to PreD3 when absorbing an UV photon. PreD3 can be converted back to ProD3, to Lumisterol, or to Tachysterol when absorbing another UV photon or can be converted to Vitamin D3 in a warm environment.
This process prevents any overdose of vitamin D3 from UV radiation with a spectrum similar to sunlight. As a comparison the solar spectra at 20°(id:14) and at 85°(id:21) solar angle are shown.
The ratio of the two solarmeters 6.2 (UVB) and 6.5 (UV index) readings has proven a useful and very simply number to acess the spectral shape in the vitamin-d3-active region.
Effective Irradiances
Effective irradiances are calculated for all ranges, actionspectra and radiometers currently present in this database.
The calculation method is a numerical implementation (Simpson's rule) of the formula
To learn more about calculating effective irradiances and radiometers I recommend this excellent report on UVB meters: Characterizing the Performance of Integral Measuring UV-Meters (pdf).
The numbers in the following tables can also be used to estimate certain (effective) irradiances from radiomer readings. Example: If the database lists
- range: UVB (US) = 13.8 µW/cm²
- radiometer: Solarmeter 6.2 = 19.6 µW/cm²
total ( 0 nm - 0 nm) 49800 µW/cm² = 498 W/m² UVC ( 0 nm - 280 nm) 0 µW/cm² = 0 W/m² non-terrestrial ( 0 nm - 290 nm) 0 µW/cm² = 0 W/m² total2 ( 250 nm - 880 nm) 49800 µW/cm² = 498 W/m² UVB (EU) ( 280 nm - 315 nm) 89.4 µW/cm² = 0.894 W/m² UVB (US) ( 280 nm - 320 nm) 184 µW/cm² = 1.84 W/m² UVA+B ( 280 nm - 380 nm) 3250 µW/cm² = 32.5 W/m² Solar UVB ( 290 nm - 315 nm) 89.4 µW/cm² = 0.894 W/m² UVA D3 regulating ( 315 nm - 335 nm) 603 µW/cm² = 6.03 W/m² UVA (EU) ( 315 nm - 380 nm) 3160 µW/cm² = 31.6 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 725 µW/cm² = 7.25 W/m² UVA (US) ( 320 nm - 380 nm) 3060 µW/cm² = 30.6 W/m² UVA1 (variant) ( 335 nm - 380 nm) 2550 µW/cm² = 25.5 W/m² UVA1 (medical) ( 340 nm - 400 nm) 3780 µW/cm² = 37.8 W/m² vis. UVA ( 350 nm - 380 nm) 1870 µW/cm² = 18.7 W/m² VIS Rep3 ( 350 nm - 600 nm) 32200 µW/cm² = 322 W/m² VIS Rep4 ( 350 nm - 700 nm) 43800 µW/cm² = 438 W/m² purple ( 380 nm - 420 nm) 3960 µW/cm² = 39.6 W/m² VIS ( 380 nm - 780 nm) 46600 µW/cm² = 466 W/m² VIS2 ( 400 nm - 680 nm) 38400 µW/cm² = 384 W/m² PAR ( 400 nm - 700 nm) 40500 µW/cm² = 405 W/m² tmp ( 400 nm - 1100 nm) 45100 µW/cm² = 451 W/m² blue ( 420 nm - 490 nm) 11200 µW/cm² = 112 W/m² green ( 490 nm - 575 nm) 11900 µW/cm² = 119 W/m² yellow ( 575 nm - 585 nm) 1320 µW/cm² = 13.2 W/m² orange ( 585 nm - 650 nm) 8070 µW/cm² = 80.7 W/m² red ( 650 nm - 780 nm) 10100 µW/cm² = 101 W/m² IRA ( 700 nm - 1400 nm) 4660 µW/cm² = 46.6 W/m² IR2 ( 720 nm - 1100 nm) 2710 µW/cm² = 27.1 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Erythema 5.37 UV-Index Pyrimidine dimerization of DNA 63.7 µW/cm² Photoceratitis 7.42 µW/cm² Photoconjunctivitis 0.134 µW/cm² DNA Damage 0.443 Vitamin D3 19.8 µW/cm² Photosynthesis 29100 µW/cm² Luminosity 105000 lx Human L-Cone 15500 µW/cm² Human M-Cone 13200 µW/cm² Human S-Cone 9040 µW/cm² CIE X 14200 µW/cm² CIE Y 14500 µW/cm² CIE Z 16800 µW/cm² PAR 189000000 mol photons Extinction preD3 191 e-3*m²/mol Extinction Tachysterol 712 e-3*m²/mol Exctincition PreD3 105000 m²/mol Extinction Lumisterol 16.5 m²/mol Exctincition Tachysterol 1250000 m²/mol Extinction 7DHC 14 m²/mol L-Cone 13100 µW/cm² M-Cone 15400 µW/cm² S-Cone 14800 µW/cm² U-Cone 8090 µW/cm² UVR - ICNIRP 2004 3.68 Rel Biol Eff Melatonin Supression 13600 µW/cm² Blue Light Hazard 10300 µW/cm² (98.8 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 21.5 µW/cm² Lumen Reptil 117000 "pseudo-lx" Vitamin D3 Degradation 38 µW/cm² Actinic UV 3.68 µW/cm² (0.352 mW/klm) Exctincition Lumisterol 27600 m²/mol Exctincition 7DHC 18600 m²/mol Exctincition Toxisterols 25700 m²/mol
Solarmeter 6.2 (UVB, pre 2010) 265 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 6.27 Leybold UVB 170 µW/cm² Leybold UVA 2310 µW/cm² Leybold UVC 0.00775 µW/cm² DeltaOhm UVB 657 µW/cm² DeltaOhm UVC 65.4 µW/cm² Vernier UVB 40.6 µW/cm² Vernier UVA 1690 µW/cm² Gröbel UVA 2570 µW/cm² Gröbel UVB 76 µW/cm² Gröbel UVC -0.0473 µW/cm² Luxmeter 106000 lx Solarmeter 6.4 (D3) 19.6 IU/min UVX-31 787 µW/cm² IL UVB 0.13 µW/cm² IL UVA 2710 µW/cm² Solarmeter 6.5 (UVI, post 2010) 5.37 UV-Index Solarmeter 6.2 (UVB, post 2010) 196 µW/cm² (Solarmeter Ratio = 36.4) Solarmeter AlGaN 6.5 UVI sensor 80.9 UV Index GenUV 7.1 UV-Index 5.57 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 513 W/m² Solarmeter 4.0 (UVA) 45.2 mW/cm² LS122 (manuf.) 0 W/m² ISM400 (first guess) 376 W/m² LS122 (assumption) 17.3 W/m² ISM400_new 318 W/m² Solarmeter 10.0 (Global Power) (assumption) 489 W/m²