solar spectrum
Melbourne, Victoria, Australia 37° 49'
17th Jan 1990, at solar noon
solar altitude 73.0°
from: B.L. Diffey / Methods 28 (2002) 4–13
Spectrum 4: 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) 6170 µW/cm² = 61.7 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) 6170 µW/cm² = 61.7 W/m² UVB (EU) ( 280 nm - 315 nm) 197 µW/cm² = 1.97 W/m² UVB (US) ( 280 nm - 320 nm) 360 µW/cm² = 3.6 W/m² UVA+B ( 280 nm - 380 nm) 4540 µW/cm² = 45.4 W/m² Solar UVB ( 290 nm - 315 nm) 197 µW/cm² = 1.97 W/m² UVA D3 regulating ( 315 nm - 335 nm) 980 µW/cm² = 9.8 W/m² UVA (EU) ( 315 nm - 380 nm) 4340 µW/cm² = 43.4 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 1130 µW/cm² = 11.3 W/m² UVA (US) ( 320 nm - 380 nm) 4180 µW/cm² = 41.8 W/m² UVA1 (variant) ( 335 nm - 380 nm) 3360 µW/cm² = 33.6 W/m² UVA1 (medical) ( 340 nm - 400 nm) 4680 µW/cm² = 46.8 W/m² vis. UVA ( 350 nm - 380 nm) 2390 µW/cm² = 23.9 W/m² VIS Rep3 ( 350 nm - 600 nm) 4030 µW/cm² = 40.3 W/m² VIS Rep4 ( 350 nm - 700 nm) 4030 µW/cm² = 40.3 W/m² purple ( 380 nm - 420 nm) 1640 µW/cm² = 16.4 W/m² VIS ( 380 nm - 780 nm) 1640 µW/cm² = 16.4 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 11.1 UV-Index Pyrimidine dimerization of DNA 140 µW/cm² Photoceratitis 15.7 µW/cm² Photoconjunctivitis 0.191 µW/cm² DNA Damage 0.648 Vitamin D3 47.7 µW/cm² Photosynthesis 0 µW/cm² Luminosity 5.58 lx Human L-Cone 0.809 µW/cm² Human M-Cone 0.742 µW/cm² Human S-Cone 18.5 µW/cm² CIE X 8.63 µW/cm² CIE Y 0.245 µW/cm² CIE Z 40.8 µW/cm² PAR 0 mol photons Extinction preD3 389 e-3*m²/mol Extinction Tachysterol 1420 e-3*m²/mol Exctincition PreD3 200000 m²/mol Extinction Lumisterol 33.2 m²/mol Exctincition Tachysterol 2310000 m²/mol Extinction 7DHC 19.8 m²/mol L-Cone 0.0833 µW/cm² M-Cone 1.3 µW/cm² S-Cone 220 µW/cm² U-Cone 6300 µW/cm² UVR - ICNIRP 2004 7.18 Rel Biol Eff Melatonin Supression 0 µW/cm² Blue Light Hazard 95 µW/cm² (17000 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 52.8 µW/cm² Lumen Reptil 8980 "pseudo-lx" Vitamin D3 Degradation 75 µW/cm² Actinic UV 7.17 µW/cm² (12900 mW/klm) Exctincition Lumisterol 56400 m²/mol Exctincition 7DHC 28900 m²/mol Exctincition Toxisterols 44400 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 502 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 14.4 Leybold UVB 339 µW/cm² Leybold UVA 3100 µW/cm² Leybold UVC 0.00357 µW/cm² DeltaOhm UVB 1110 µW/cm² DeltaOhm UVC 110 µW/cm² Vernier UVB 111 µW/cm² Vernier UVA 2770 µW/cm² Gröbel UVA 3550 µW/cm² Gröbel UVB 157 µW/cm² Gröbel UVC -0.0874 µW/cm² Luxmeter 6.2 lx Solarmeter 6.4 (D3) 45.1 IU/min UVX-31 1300 µW/cm² IL UVB 0.234 µW/cm² IL UVA 3620 µW/cm² Solarmeter 6.5 (UVI, post 2010) 12.5 UV-Index Solarmeter 6.2 (UVB, post 2010) 361 µW/cm² (Solarmeter Ratio = 28.9) Solarmeter AlGaN 6.5 UVI sensor 180 UV Index GenUV 7.1 UV-Index 11.2 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 28 W/m² Solarmeter 4.0 (UVA) 55.4 mW/cm² LS122 (manuf.) 0 W/m² ISM400 (first guess) 4.65 W/m² LS122 (assumption) 0 W/m² ISM400_new 2.38 W/m² Solarmeter 10.0 (Global Power) (assumption) 14.1 W/m²