Reptile Lamp Database

Spectrum 252: BEL18 Edit
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Full Spectrum

Measurement

Brand other
other
Lamp Product Chinese Prototype 5.0 T8 18W
Lamp ID BEL18 (12/2008)
Spectrometer USB2000+
Ballast - no ballast or default/unknown ballast -
Reflector
Distance 10 cm
Age 105 hours
Originator (measurement) Frances Baines
Database entry created: Maren 10/Jun/2010 ; updated: Sarina Wunderlich 27/Feb/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 ( 0.26 ; 0.26 ) ( 0.25 ; 0.41 ) ( 0.15 ; 0.21 ; 0.35 )
CCT 20000 Kelvin 10000 Kelvin 12000 Kelvin
distance 0.077 0.066
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) 645 µW/cm² = 6.45 W/m²
UVC ( 0 nm - 280 nm) 0.562 µW/cm² = 0.00562 W/m²
non-terrestrial ( 0 nm - 290 nm) 0.929 µW/cm² = 0.00929 W/m²
total2 ( 250 nm - 880 nm) 645 µW/cm² = 6.45 W/m²
UVB (EU) ( 280 nm - 315 nm) 25.4 µW/cm² = 0.254 W/m²
UVB (US) ( 280 nm - 320 nm) 37.3 µW/cm² = 0.373 W/m²
UVA+B ( 280 nm - 380 nm) 233 µW/cm² = 2.33 W/m²
Solar UVB ( 290 nm - 315 nm) 25 µW/cm² = 0.25 W/m²
UVA D3 regulating ( 315 nm - 335 nm) 61.6 µW/cm² = 0.616 W/m²
UVA (EU) ( 315 nm - 380 nm) 208 µW/cm² = 2.08 W/m²
UVA2 (medical definition) ( 320 nm - 340 nm) 70.5 µW/cm² = 0.705 W/m²
UVA (US) ( 320 nm - 380 nm) 196 µW/cm² = 1.96 W/m²
UVA1 (variant) ( 335 nm - 380 nm) 146 µW/cm² = 1.46 W/m²
UVA1 (medical) ( 340 nm - 400 nm) 147 µW/cm² = 1.47 W/m²
vis. UVA ( 350 nm - 380 nm) 86.5 µW/cm² = 0.865 W/m²
VIS Rep3 ( 350 nm - 600 nm) 417 µW/cm² = 4.17 W/m²
VIS Rep4 ( 350 nm - 700 nm) 473 µW/cm² = 4.73 W/m²
purple ( 380 nm - 420 nm) 57.8 µW/cm² = 0.578 W/m²
VIS ( 380 nm - 780 nm) 402 µW/cm² = 4.02 W/m²
PAR ( 400 nm - 700 nm) 365 µW/cm² = 3.65 W/m²
blue ( 420 nm - 490 nm) 143 µW/cm² = 1.43 W/m²
green ( 490 nm - 575 nm) 105 µW/cm² = 1.05 W/m²
yellow ( 575 nm - 585 nm) 12.7 µW/cm² = 0.127 W/m²
orange ( 585 nm - 650 nm) 44.6 µW/cm² = 0.446 W/m²
red ( 650 nm - 780 nm) 38.2 µW/cm² = 0.382 W/m²
IRA ( 700 nm - 1400 nm) 25.4 µW/cm² = 0.254 W/m²
IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 2.57 UV-Index
Pyrimidine dimerization of DNA 15.5 µW/cm²
Photoceratitis 3.69 µW/cm²
Photoconjunctivitis 0.625 µW/cm²
DNA Damage 0.975
Vitamin D3 8.73 µW/cm²
Photosynthesis 268 µW/cm²
Luminosity 870 lx
Human L-Cone 125 µW/cm²
Human M-Cone 117 µW/cm²
Human S-Cone 123 µW/cm²
CIE X 118 µW/cm²
CIE Y 120 µW/cm²
CIE Z 225 µW/cm²
PAR 1720000 mol photons
Extinction preD3 52.6 e-3*m²/mol
Extinction Tachysterol 182 e-3*m²/mol
Exctincition PreD3 29200 m²/mol
Extinction Lumisterol 17.1 m²/mol
Exctincition Tachysterol 261000 m²/mol
Extinction 7DHC 19.6 m²/mol
L-Cone 99.3 µW/cm²
M-Cone 136 µW/cm²
S-Cone 223 µW/cm²
U-Cone 187 µW/cm²
UVR - ICNIRP 2004 2.76 Rel Biol Eff
Melatonin Supression 160 µW/cm²
Blue Light Hazard 141 µW/cm² (162 µW/cm² per 1000 lx)
CIE 174:2006 PreVit D3 9.45 µW/cm²
Lumen Reptil 1310 "pseudo-lx"
Vitamin D3 Degradation 8.13 µW/cm²
Actinic UV 2.73 µW/cm² (31.4 mW/klm)
Exctincition Lumisterol 21100 m²/mol
Exctincition 7DHC 23000 m²/mol
Exctincition Toxisterols 6030 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 46.6 µW/cm²
Solarmeter 6.5 (UV-Index, pre 2010) 2.58
Leybold UVB 32.8 µW/cm²
Leybold UVA 146 µW/cm²
Leybold UVC 0.422 µW/cm²
DeltaOhm UVB 80.7 µW/cm²
DeltaOhm UVC 10.1 µW/cm²
Vernier UVB 12.7 µW/cm²
Vernier UVA 135 µW/cm²
Gröbel UVA 177 µW/cm²
Gröbel UVB 18.5 µW/cm²
Gröbel UVC 0.445 µW/cm²
Solarmeter 6.4 (D3) 8.06 IU/min
UVX-31 91.6 µW/cm²
IL UVB 0.021 µW/cm²
IL UVA 165 µW/cm²
Solarmeter 6.5 (UVI, post 2010) 1.96 UV-Index
Solarmeter 6.2 (UVB, post 2010) 30.1 µW/cm² (Solarmeter Ratio = 15.3)
Solarmeter AlGaN 6.5 UVI sensor 21.5 UV Index
GenUV 7.1 UV-Index 1.21 UV-Index
Solarmeter 10.0 (Global Power) 4.89 W/m²
Solarmeter 4.0 (UVA) 2.22 mW/cm²
LS122 0.00375 W/m²
ISM400 2.7 W/m²