solar spectrum
Albuquerque, New Mexico, USA, N35° 06'
3rd July 2001, at 12 noon local time
solar altitude 77.6°
from:
B.L. Diffey / Methods 28 (2002) 4–13
Spectrum 3: SUN Edit
DeleteMeasurement
| Brand |
other other |
|---|---|
| Lamp Product |
Sun Direct sunlight |
| Lamp ID |
SUN (01/2000) |
| Spectrometer | - |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 0 cm |
| Age | 0 hours |
| Originator (measurement) | Publication |
Database entry created:
Sarina Wunderlich
9/Nov/2009 ; updated:
Sarina Wunderlich
9/Oct/2011
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 - 400 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 | ( 0.17 ; 0.0049 ) | ( 0.0002 ; 0.034 ) | ( 1.3E-5 ; 0.0002 ; 0.034 ) |
| CCT | 0 Kelvin | 0 Kelvin | 0 Kelvin |
| distance | 0 | 0 | |
| 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) 5140 µW/cm² = 51.4 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) 5140 µW/cm² = 51.4 W/m² UVB (EU) ( 280 nm - 315 nm) 155 µW/cm² = 1.55 W/m² UVB (US) ( 280 nm - 320 nm) 290 µW/cm² = 2.9 W/m² UVA+B ( 280 nm - 380 nm) 3740 µW/cm² = 37.4 W/m² Solar UVB ( 290 nm - 315 nm) 155 µW/cm² = 1.55 W/m² UVA D3 regulating ( 315 nm - 335 nm) 812 µW/cm² = 8.12 W/m² UVA (EU) ( 315 nm - 380 nm) 3590 µW/cm² = 35.9 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 931 µW/cm² = 9.31 W/m² UVA (US) ( 320 nm - 380 nm) 3450 µW/cm² = 34.5 W/m² UVA1 (variant) ( 335 nm - 380 nm) 2770 µW/cm² = 27.7 W/m² UVA1 (medical) ( 340 nm - 400 nm) 3920 µW/cm² = 39.2 W/m² vis. UVA ( 350 nm - 380 nm) 1980 µW/cm² = 19.8 W/m² VIS Rep3 ( 350 nm - 600 nm) 3380 µW/cm² = 33.8 W/m² VIS Rep4 ( 350 nm - 700 nm) 3380 µW/cm² = 33.8 W/m² purple ( 380 nm - 420 nm) 1400 µW/cm² = 14 W/m² VIS ( 380 nm - 780 nm) 1400 µW/cm² = 14 W/m² VIS2 ( 400 nm - 680 nm) 0 µW/cm² = 0 W/m² PAR ( 400 nm - 700 nm) 0 µW/cm² = 0 W/m² tmp ( 400 nm - 1100 nm) 0 µW/cm² = 0 W/m² blue ( 420 nm - 490 nm) 0 µW/cm² = 0 W/m² green ( 490 nm - 575 nm) 0 µW/cm² = 0 W/m² yellow ( 575 nm - 585 nm) 0 µW/cm² = 0 W/m² orange ( 585 nm - 650 nm) 0 µW/cm² = 0 W/m² red ( 650 nm - 780 nm) 0 µW/cm² = 0 W/m² IRA ( 700 nm - 1400 nm) 0 µW/cm² = 0 W/m² IR2 ( 720 nm - 1100 nm) 0 µW/cm² = 0 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 8.75 UV-Index Pyrimidine dimerization of DNA 111 µW/cm² Photoceratitis 12.3 µW/cm² Photoconjunctivitis 0.145 µW/cm² DNA Damage 0.495 Vitamin D3 37.3 µW/cm² Photosynthesis 0 µW/cm² Luminosity 4.83 lx Human L-Cone 0.7 µW/cm² Human M-Cone 0.642 µW/cm² Human S-Cone 16 µW/cm² CIE X 7.44 µW/cm² CIE Y 0.211 µW/cm² CIE Z 35.2 µW/cm² PAR 0 mol photons Extinction preD3 312 e-3*m²/mol Extinction Tachysterol 1140 e-3*m²/mol Exctincition PreD3 161000 m²/mol Extinction Lumisterol 25.5 m²/mol Exctincition Tachysterol 1870000 m²/mol Extinction 7DHC 15 m²/mol L-Cone 0.0718 µW/cm² M-Cone 1.13 µW/cm² S-Cone 190 µW/cm² U-Cone 5360 µW/cm² UVR - ICNIRP 2004 5.62 Rel Biol Eff Melatonin Supression 0 µW/cm² Blue Light Hazard 80.4 µW/cm² (16700 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 41.2 µW/cm² Lumen Reptil 7650 "pseudo-lx" Vitamin D3 Degradation 60.4 µW/cm² Actinic UV 5.6 µW/cm² (11600 mW/klm) Exctincition Lumisterol 44000 m²/mol Exctincition 7DHC 22100 m²/mol Exctincition Toxisterols 36100 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 407 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 11.3 Leybold UVB 273 µW/cm² Leybold UVA 2570 µW/cm² Leybold UVC 0.00247 µW/cm² DeltaOhm UVB 913 µW/cm² DeltaOhm UVC 90 µW/cm² Vernier UVB 87.2 µW/cm² Vernier UVA 2280 µW/cm² Gröbel UVA 2930 µW/cm² Gröbel UVB 126 µW/cm² Gröbel UVC -0.071 µW/cm² Luxmeter 5.37 lx Solarmeter 6.4 (D3) 35.5 IU/min UVX-31 1060 µW/cm² IL UVB 0.19 µW/cm² IL UVA 3000 µW/cm² Solarmeter 6.5 (UVI, post 2010) 9.84 UV-Index Solarmeter 6.2 (UVB, post 2010) 294 µW/cm² (Solarmeter Ratio = 29.9) Solarmeter AlGaN 6.5 UVI sensor 143 UV Index GenUV 7.1 UV-Index 9.02 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 23.4 W/m² Solarmeter 4.0 (UVA) 46.3 mW/cm² LS122 (manuf.) 0 W/m² ISM400 (first guess) 3.92 W/m² LS122 (assumption) 0 W/m² ISM400_new 2.01 W/m² Solarmeter 10.0 (Global Power) (assumption) 11.9 W/m²