2007-05-02; 13:03 (solar altitude 52.0)
direct sun
Corrected data with value at 290nm converted to zero to loer baseline, and all negative values to zero
Spectrum 444: 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 | 0.042 | 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) 57100 µW/cm² = 571 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) 57000 µW/cm² = 570 W/m² UVB (EU) ( 280 nm - 315 nm) 42.2 µW/cm² = 0.422 W/m² UVB (US) ( 280 nm - 320 nm) 97.4 µW/cm² = 0.974 W/m² UVA+B ( 280 nm - 380 nm) 2120 µW/cm² = 21.2 W/m² Solar UVB ( 290 nm - 315 nm) 42.2 µW/cm² = 0.422 W/m² UVA D3 regulating ( 315 nm - 335 nm) 366 µW/cm² = 3.66 W/m² UVA (EU) ( 315 nm - 380 nm) 2080 µW/cm² = 20.8 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 444 µW/cm² = 4.44 W/m² UVA (US) ( 320 nm - 380 nm) 2020 µW/cm² = 20.2 W/m² UVA1 (variant) ( 335 nm - 380 nm) 1710 µW/cm² = 17.1 W/m² UVA1 (medical) ( 340 nm - 400 nm) 2700 µW/cm² = 27 W/m² vis. UVA ( 350 nm - 380 nm) 1280 µW/cm² = 12.8 W/m² VIS Rep3 ( 350 nm - 600 nm) 28100 µW/cm² = 281 W/m² VIS Rep4 ( 350 nm - 700 nm) 40000 µW/cm² = 400 W/m² purple ( 380 nm - 420 nm) 3150 µW/cm² = 31.5 W/m² VIS ( 380 nm - 780 nm) 46300 µW/cm² = 463 W/m² PAR ( 400 nm - 700 nm) 37600 µW/cm² = 376 W/m² blue ( 420 nm - 490 nm) 9050 µW/cm² = 90.5 W/m² green ( 490 nm - 575 nm) 11300 µW/cm² = 113 W/m² yellow ( 575 nm - 585 nm) 1350 µW/cm² = 13.5 W/m² orange ( 585 nm - 650 nm) 8130 µW/cm² = 81.3 W/m² red ( 650 nm - 780 nm) 13300 µW/cm² = 133 W/m² IRA ( 700 nm - 1400 nm) 16200 µW/cm² = 162 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 2.19 UV-Index Pyrimidine dimerization of DNA 31.5 µW/cm² Photoceratitis 2.74 µW/cm² Photoconjunctivitis 0.0229 µW/cm² DNA Damage 0.0721 Vitamin D3 7.41 µW/cm² Photosynthesis 26700 µW/cm² Luminosity 101000 lx Human L-Cone 15100 µW/cm² Human M-Cone 12600 µW/cm² Human S-Cone 7370 µW/cm² CIE X 13600 µW/cm² CIE Y 14000 µW/cm² CIE Z 13700 µW/cm² PAR 178000000 mol photons Extinction preD3 96.5 e-3*m²/mol Extinction Tachysterol 367 e-3*m²/mol Exctincition PreD3 54900 m²/mol Extinction Lumisterol 3.61 m²/mol Exctincition Tachysterol 682000 m²/mol Extinction 7DHC 1.6 m²/mol L-Cone 12900 µW/cm² M-Cone 13500 µW/cm² S-Cone 12000 µW/cm² U-Cone 6170 µW/cm² UVR - ICNIRP 2004 1.16 Rel Biol Eff Melatonin Supression 11300 µW/cm² Blue Light Hazard 8440 µW/cm² (83.5 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 7.88 µW/cm² Lumen Reptil 105000 "pseudo-lx" Vitamin D3 Degradation 20.1 µW/cm² Actinic UV 1.18 µW/cm² (0.117 mW/klm) Exctincition Lumisterol 8670 m²/mol Exctincition 7DHC 2970 m²/mol Exctincition Toxisterols 15000 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 149 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 2.52 Leybold UVB 92.3 µW/cm² Leybold UVA 1520 µW/cm² Leybold UVC 0.000533 µW/cm² DeltaOhm UVB 392 µW/cm² DeltaOhm UVC 37.7 µW/cm² Vernier UVB 17.6 µW/cm² Vernier UVA 1060 µW/cm² Gröbel UVA 1670 µW/cm² Gröbel UVB 38.4 µW/cm² Gröbel UVC -0.0306 µW/cm² Solarmeter 6.4 (D3) 7.89 IU/min UVX-31 474 µW/cm² IL UVB 0.0739 µW/cm² IL UVA 1790 µW/cm² Solarmeter 6.5 (UVI, post 2010) 2.28 UV-Index Solarmeter 6.2 (UVB, post 2010) 112 µW/cm² (Solarmeter Ratio = 49.4) Solarmeter AlGaN 6.5 UVI sensor 39.3 UV Index GenUV 7.1 UV-Index 2.97 UV-Index Solarmeter 10.0 (Global Power) 681 W/m² Solarmeter 4.0 (UVA) 31.2 mW/cm² LS122 9.43 W/m² ISM400 620 W/m²