Reptile Lamp Database

Spectrum 34: SUN Edit
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Full Spectrum

Daylight just before sunset on a horizontal plane in Lund

LARS OLOF BJÖRN. 2007. The Science of Life and Light. 2nd ed. New York: Springer 978-0-387-72654-0.

Measurement

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 28/Jan/2010 ; 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.

Spectrum in the visible wavelength range

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, 338451, 511513 ), indicated by crosses, coloured in the appriximate colour perceived by a human.

Human (CIE) 3 cone reptile 4 cone reptile
Cone Excitation
Colour Coordinate ( 0.31 ; 0.32 ) ( 0.38 ; 0.38 ) ( 0.24 ; 0.29 ; 0.28 )
CCT 6700 Kelvin 5200 Kelvin 5800 Kelvin
distance 0.035 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.

Spectrum in the vitamin D3 active wavelength range

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
then any Solarmeter 6.2 reading multiplied with 0.7 (0.7=13.8/19.6) is an estimate of UVB irradiance for this specific lamp. If you do so, always make sure, that the calculated (effective) irradiance is valid. The calculated value is not valid, if the lamp's spectrum is not measured in the relevant range.

Ranges
total ( 0 nm - 0 nm) 1240 µW/cm² = 12.4 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) 1240 µW/cm² = 12.4 W/m²
UVB (EU) ( 280 nm - 315 nm) 0.192 µW/cm² = 0.00192 W/m²
UVB (US) ( 280 nm - 320 nm) 0.639 µW/cm² = 0.00639 W/m²
UVA+B ( 280 nm - 380 nm) 81 µW/cm² = 0.81 W/m²
Solar UVB ( 290 nm - 315 nm) 0.192 µW/cm² = 0.00192 W/m²
UVA D3 regulating ( 315 nm - 335 nm) 10.1 µW/cm² = 0.101 W/m²
UVA (EU) ( 315 nm - 380 nm) 80.8 µW/cm² = 0.808 W/m²
UVA2 (medical definition) ( 320 nm - 340 nm) 15.7 µW/cm² = 0.157 W/m²
UVA (US) ( 320 nm - 380 nm) 80.3 µW/cm² = 0.803 W/m²
UVA1 (variant) ( 335 nm - 380 nm) 70.6 µW/cm² = 0.706 W/m²
UVA1 (medical) ( 340 nm - 400 nm) 105 µW/cm² = 1.05 W/m²
vis. UVA ( 350 nm - 380 nm) 51.2 µW/cm² = 0.512 W/m²
VIS Rep3 ( 350 nm - 600 nm) 718 µW/cm² = 7.18 W/m²
VIS Rep4 ( 350 nm - 700 nm) 1010 µW/cm² = 10.1 W/m²
purple ( 380 nm - 420 nm) 98.2 µW/cm² = 0.982 W/m²
VIS ( 380 nm - 780 nm) 1160 µW/cm² = 11.6 W/m²
PAR ( 400 nm - 700 nm) 923 µW/cm² = 9.23 W/m²
blue ( 420 nm - 490 nm) 244 µW/cm² = 2.44 W/m²
green ( 490 nm - 575 nm) 263 µW/cm² = 2.63 W/m²
yellow ( 575 nm - 585 nm) 25.5 µW/cm² = 0.255 W/m²
orange ( 585 nm - 650 nm) 180 µW/cm² = 1.8 W/m²
red ( 650 nm - 780 nm) 351 µW/cm² = 3.51 W/m²
IRA ( 700 nm - 1400 nm) 198 µW/cm² = 1.98 W/m²
IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 0.0305 UV-Index
Pyrimidine dimerization of DNA 0.288 µW/cm²
Photoceratitis 0.00831 µW/cm²
Photoconjunctivitis 0 µW/cm²
DNA Damage 0.000211
Vitamin D3 0.0198 µW/cm²
Photosynthesis 673 µW/cm²
Luminosity 2260 lx
Human L-Cone 336 µW/cm²
Human M-Cone 285 µW/cm²
Human S-Cone 199 µW/cm²
CIE X 307 µW/cm²
CIE Y 312 µW/cm²
CIE Z 368 µW/cm²
PAR 4350000 mol photons
Extinction preD3 0.922 e-3*m²/mol
Extinction Tachysterol 4 e-3*m²/mol
Exctincition PreD3 984 m²/mol
Extinction Lumisterol 0.00303 m²/mol
Exctincition Tachysterol 14000 m²/mol
Extinction 7DHC 0 m²/mol
L-Cone 284 µW/cm²
M-Cone 337 µW/cm²
S-Cone 330 µW/cm²
U-Cone 210 µW/cm²
UVR - ICNIRP 2004 0.0185 Rel Biol Eff
Melatonin Supression 299 µW/cm²
Blue Light Hazard 229 µW/cm² (101 µW/cm² per 1000 lx)
CIE 174:2006 PreVit D3 0.0146 µW/cm²
Lumen Reptil 2620 "pseudo-lx"
Vitamin D3 Degradation 0.258 µW/cm²
Actinic UV 0.0185 µW/cm² (0.082 mW/klm)
Exctincition Lumisterol 41.6 m²/mol
Exctincition 7DHC 7.67 m²/mol
Exctincition Toxisterols 400 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 2.03 µW/cm²
Solarmeter 6.5 (UV-Index, pre 2010) 0.0194
Leybold UVB 1.08 µW/cm²
Leybold UVA 63.3 µW/cm²
Leybold UVC 0 µW/cm²
DeltaOhm UVB 10.6 µW/cm²
DeltaOhm UVC 0.55 µW/cm²
Vernier UVB 0.0584 µW/cm²
Vernier UVA 47.1 µW/cm²
Gröbel UVA 67.5 µW/cm²
Gröbel UVB 0.531 µW/cm²
Gröbel UVC -0.000252 µW/cm²
Solarmeter 6.4 (D3) 0.0605 IU/min
UVX-31 14.5 µW/cm²
IL UVB 0.00166 µW/cm²
IL UVA 72.9 µW/cm²
Solarmeter 6.5 (UVI, post 2010) 0.0164 UV-Index
Solarmeter 6.2 (UVB, post 2010) 1.73 µW/cm² (Solarmeter Ratio = 105)
Solarmeter AlGaN 6.5 UVI sensor 0.237 UV Index
GenUV 7.1 UV-Index 0.0352 UV-Index
Solarmeter 10.0 (Global Power) 13.3 W/m²
Solarmeter 4.0 (UVA) 1.2 mW/cm²
LS122 0 W/m²
ISM400 10.5 W/m²