2010-05-23; 14:00 (solar altitude 57.3)
plum tree shade
Spectrum 433: SUN Edit
DeleteMeasurement
| Brand |
other other |
|---|---|
| Lamp Product |
Sun Direct sunlight |
| Lamp ID |
SUN (01/2000) |
| Spectrometer | USB2000+ (2) |
| 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 | ( 0.26 ; 0.27 ) | ( 0.29 ; 0.38 ) | ( 0.16 ; 0.24 ; 0.32 ) |
| CCT | 15000 Kelvin | 8100 Kelvin | 9500 Kelvin |
| distance | 0.046 | 0.048 | |
| 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) 2530 µW/cm² = 25.3 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) 2520 µW/cm² = 25.2 W/m² UVB (EU) ( 280 nm - 315 nm) 13.7 µW/cm² = 0.137 W/m² UVB (US) ( 280 nm - 320 nm) 26.6 µW/cm² = 0.266 W/m² UVA+B ( 280 nm - 380 nm) 328 µW/cm² = 3.28 W/m² Solar UVB ( 290 nm - 315 nm) 13.7 µW/cm² = 0.137 W/m² UVA D3 regulating ( 315 nm - 335 nm) 80.1 µW/cm² = 0.801 W/m² UVA (EU) ( 315 nm - 380 nm) 314 µW/cm² = 3.14 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 92.3 µW/cm² = 0.923 W/m² UVA (US) ( 320 nm - 380 nm) 301 µW/cm² = 3.01 W/m² UVA1 (variant) ( 335 nm - 380 nm) 234 µW/cm² = 2.34 W/m² UVA1 (medical) ( 340 nm - 400 nm) 304 µW/cm² = 3.04 W/m² vis. UVA ( 350 nm - 380 nm) 160 µW/cm² = 1.6 W/m² VIS Rep3 ( 350 nm - 600 nm) 1250 µW/cm² = 12.5 W/m² VIS Rep4 ( 350 nm - 700 nm) 1440 µW/cm² = 14.4 W/m² purple ( 380 nm - 420 nm) 240 µW/cm² = 2.4 W/m² VIS ( 380 nm - 780 nm) 1650 µW/cm² = 16.5 W/m² PAR ( 400 nm - 700 nm) 1180 µW/cm² = 11.8 W/m² blue ( 420 nm - 490 nm) 430 µW/cm² = 4.3 W/m² green ( 490 nm - 575 nm) 347 µW/cm² = 3.47 W/m² yellow ( 575 nm - 585 nm) 31.1 µW/cm² = 0.311 W/m² orange ( 585 nm - 650 nm) 154 µW/cm² = 1.54 W/m² red ( 650 nm - 780 nm) 442 µW/cm² = 4.42 W/m² IRA ( 700 nm - 1400 nm) 921 µW/cm² = 9.21 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 0.649 UV-Index Pyrimidine dimerization of DNA 9.37 µW/cm² Photoceratitis 0.941 µW/cm² Photoconjunctivitis 0.00893 µW/cm² DNA Damage 0.0276 Vitamin D3 2.71 µW/cm² Photosynthesis 879 µW/cm² Luminosity 2790 lx Human L-Cone 402 µW/cm² Human M-Cone 376 µW/cm² Human S-Cone 366 µW/cm² CIE X 367 µW/cm² CIE Y 384 µW/cm² CIE Z 661 µW/cm² PAR 5430000 mol photons Extinction preD3 27.2 e-3*m²/mol Extinction Tachysterol 100 e-3*m²/mol Exctincition PreD3 14200 m²/mol Extinction Lumisterol 1.53 m²/mol Exctincition Tachysterol 168000 m²/mol Extinction 7DHC 0.702 m²/mol L-Cone 319 µW/cm² M-Cone 482 µW/cm² S-Cone 644 µW/cm² U-Cone 551 µW/cm² UVR - ICNIRP 2004 0.368 Rel Biol Eff Melatonin Supression 521 µW/cm² Blue Light Hazard 432 µW/cm² (155 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 2.98 µW/cm² Lumen Reptil 4190 "pseudo-lx" Vitamin D3 Degradation 5.43 µW/cm² Actinic UV 0.371 µW/cm² (1.33 mW/klm) Exctincition Lumisterol 3050 m²/mol Exctincition 7DHC 1160 m²/mol Exctincition Toxisterols 3360 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 37.3 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 0.844 Leybold UVB 24.7 µW/cm² Leybold UVA 222 µW/cm² Leybold UVC 2.32E-5 µW/cm² DeltaOhm UVB 87.4 µW/cm² DeltaOhm UVC 8.86 µW/cm² Vernier UVB 6.2 µW/cm² Vernier UVA 181 µW/cm² Gröbel UVA 258 µW/cm² Gröbel UVB 10.8 µW/cm² Gröbel UVC -0.00756 µW/cm² Solarmeter 6.4 (D3) 2.64 IU/min UVX-31 100 µW/cm² IL UVB 0.0174 µW/cm² IL UVA 257 µW/cm² Solarmeter 6.5 (UVI, post 2010) 0.755 UV-Index Solarmeter 6.2 (UVB, post 2010) 27.7 µW/cm² (Solarmeter Ratio = 36.7) Solarmeter AlGaN 6.5 UVI sensor 12 UV Index GenUV 7.1 UV-Index 0.783 UV-Index Solarmeter 10.0 (Global Power) 28.2 W/m² Solarmeter 4.0 (UVA) 3.95 mW/cm² LS122 0.617 W/m² ISM400 26.4 W/m²