2007-05-02; 12:47 (solar altitude 52.8)
direct sun
Corrected data with value at 290nm converted to zero to loer baseline, and all negative values to zero
Spectrum 445: SUN Edit
DeleteMeasurement
| Brand |
other other |
|---|---|
| Lamp Product |
Sun Direct sunlight |
| Lamp ID |
SUN (01/2000) |
| Spectrometer | USB 2000 |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 0 cm |
| Age | 0 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Sarina Wunderlich
12/Jan/2012 ; updated:
Sarina Wunderlich
12/Jan/2012
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.
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 | ( 0.33 ; 0.34 ) | ( 0.43 ; 0.38 ) | ( 0.29 ; 0.3 ; 0.27 ) |
| CCT | 5600 Kelvin | 4600 Kelvin | 5000 Kelvin |
| distance | 0.041 | 0.038 | |
| 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
Ranges
total ( 0 nm - 0 nm) 55300 µW/cm² = 553 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) 55200 µW/cm² = 552 W/m² UVB (EU) ( 280 nm - 315 nm) 39.8 µW/cm² = 0.398 W/m² UVB (US) ( 280 nm - 320 nm) 92.8 µW/cm² = 0.928 W/m² UVA+B ( 280 nm - 380 nm) 2030 µW/cm² = 20.3 W/m² Solar UVB ( 290 nm - 315 nm) 39.8 µW/cm² = 0.398 W/m² UVA D3 regulating ( 315 nm - 335 nm) 351 µW/cm² = 3.51 W/m² UVA (EU) ( 315 nm - 380 nm) 1990 µW/cm² = 19.9 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 426 µW/cm² = 4.26 W/m² UVA (US) ( 320 nm - 380 nm) 1940 µW/cm² = 19.4 W/m² UVA1 (variant) ( 335 nm - 380 nm) 1640 µW/cm² = 16.4 W/m² UVA1 (medical) ( 340 nm - 400 nm) 2590 µW/cm² = 25.9 W/m² vis. UVA ( 350 nm - 380 nm) 1230 µW/cm² = 12.3 W/m² VIS Rep3 ( 350 nm - 600 nm) 27000 µW/cm² = 270 W/m² VIS Rep4 ( 350 nm - 700 nm) 38600 µW/cm² = 386 W/m² purple ( 380 nm - 420 nm) 3020 µW/cm² = 30.2 W/m² VIS ( 380 nm - 780 nm) 44800 µW/cm² = 448 W/m² VIS2 ( 400 nm - 680 nm) 34200 µW/cm² = 342 W/m² PAR ( 400 nm - 700 nm) 36300 µW/cm² = 363 W/m² tmp ( 400 nm - 1100 nm) 52200 µW/cm² = 522 W/m² blue ( 420 nm - 490 nm) 8690 µW/cm² = 86.9 W/m² green ( 490 nm - 575 nm) 10900 µW/cm² = 109 W/m² yellow ( 575 nm - 585 nm) 1300 µW/cm² = 13 W/m² orange ( 585 nm - 650 nm) 7870 µW/cm² = 78.7 W/m² red ( 650 nm - 780 nm) 13000 µW/cm² = 130 W/m² IRA ( 700 nm - 1400 nm) 15900 µW/cm² = 159 W/m² IR2 ( 720 nm - 1100 nm) 13900 µW/cm² = 139 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 2.02 UV-Index Pyrimidine dimerization of DNA 29.8 µW/cm² Photoceratitis 2.49 µW/cm² Photoconjunctivitis 0.0163 µW/cm² DNA Damage 0.0504 Vitamin D3 6.77 µW/cm² Photosynthesis 25800 µW/cm² Luminosity 97600 lx Human L-Cone 14600 µW/cm² Human M-Cone 12100 µW/cm² Human S-Cone 7080 µW/cm² CIE X 13200 µW/cm² CIE Y 13500 µW/cm² CIE Z 13200 µW/cm² PAR 172000000 mol photons Extinction preD3 91.2 e-3*m²/mol Extinction Tachysterol 348 e-3*m²/mol Exctincition PreD3 52000 m²/mol Extinction Lumisterol 2.91 m²/mol Exctincition Tachysterol 649000 m²/mol Extinction 7DHC 0.893 m²/mol L-Cone 12500 µW/cm² M-Cone 13000 µW/cm² S-Cone 11500 µW/cm² U-Cone 5910 µW/cm² UVR - ICNIRP 2004 1.03 Rel Biol Eff Melatonin Supression 10800 µW/cm² Blue Light Hazard 8100 µW/cm² (83 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 7.16 µW/cm² Lumen Reptil 101000 "pseudo-lx" Vitamin D3 Degradation 19.1 µW/cm² Actinic UV 1.04 µW/cm² (0.107 mW/klm) Exctincition Lumisterol 7630 m²/mol Exctincition 7DHC 2110 m²/mol Exctincition Toxisterols 14300 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 142 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 2.32 Leybold UVB 87.9 µW/cm² Leybold UVA 1460 µW/cm² Leybold UVC 0 µW/cm² DeltaOhm UVB 375 µW/cm² DeltaOhm UVC 36 µW/cm² Vernier UVB 16.4 µW/cm² Vernier UVA 1010 µW/cm² Gröbel UVA 1600 µW/cm² Gröbel UVB 36.3 µW/cm² Gröbel UVC -0.03 µW/cm² Luxmeter 98600 lx Solarmeter 6.4 (D3) 7.25 IU/min UVX-31 454 µW/cm² IL UVB 0.0705 µW/cm² IL UVA 1720 µW/cm² Solarmeter 6.5 (UVI, post 2010) 2.11 UV-Index Solarmeter 6.2 (UVB, post 2010) 107 µW/cm² (Solarmeter Ratio = 50.9) Solarmeter AlGaN 6.5 UVI sensor 37 UV Index GenUV 7.1 UV-Index 2.82 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 661 W/m² Solarmeter 4.0 (UVA) 29.9 mW/cm² LS122 (manuf.) 15.4 W/m² ISM400 (first guess) 604 W/m² LS122 (assumption) 34.1 W/m² ISM400_new 582 W/m² Solarmeter 10.0 (Global Power) (assumption) 652 W/m²