Spectrum 251: BEL18 Edit
DeleteMeasurement
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 | 1 hours |
Originator (measurement) | Frances Baines |
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 | ( 0.25 ; 0.26 ) | ( 0.25 ; 0.4 ) | ( 0.15 ; 0.21 ; 0.34 ) |
CCT | 20000 Kelvin | 10000 Kelvin | 12000 Kelvin |
distance | 0.072 | 0.062 | |
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
total ( 0 nm - 0 nm) 642 µW/cm² = 6.42 W/m² UVC ( 0 nm - 280 nm) 0.758 µW/cm² = 0.00758 W/m² non-terrestrial ( 0 nm - 290 nm) 1.29 µW/cm² = 0.0129 W/m² total2 ( 250 nm - 880 nm) 642 µW/cm² = 6.42 W/m² UVB (EU) ( 280 nm - 315 nm) 28.9 µW/cm² = 0.289 W/m² UVB (US) ( 280 nm - 320 nm) 40.8 µW/cm² = 0.408 W/m² UVA+B ( 280 nm - 380 nm) 238 µW/cm² = 2.38 W/m² Solar UVB ( 290 nm - 315 nm) 28.3 µW/cm² = 0.283 W/m² UVA D3 regulating ( 315 nm - 335 nm) 61.2 µW/cm² = 0.612 W/m² UVA (EU) ( 315 nm - 380 nm) 209 µW/cm² = 2.09 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 70.1 µW/cm² = 0.701 W/m² UVA (US) ( 320 nm - 380 nm) 198 µW/cm² = 1.98 W/m² UVA1 (variant) ( 335 nm - 380 nm) 148 µW/cm² = 1.48 W/m² UVA1 (medical) ( 340 nm - 400 nm) 149 µW/cm² = 1.49 W/m² vis. UVA ( 350 nm - 380 nm) 87.7 µW/cm² = 0.877 W/m² VIS Rep3 ( 350 nm - 600 nm) 411 µW/cm² = 4.11 W/m² VIS Rep4 ( 350 nm - 700 nm) 467 µW/cm² = 4.67 W/m² purple ( 380 nm - 420 nm) 56.3 µW/cm² = 0.563 W/m² VIS ( 380 nm - 780 nm) 394 µW/cm² = 3.94 W/m² VIS2 ( 400 nm - 680 nm) 350 µW/cm² = 3.5 W/m² PAR ( 400 nm - 700 nm) 357 µW/cm² = 3.57 W/m² tmp ( 400 nm - 1100 nm) 382 µW/cm² = 3.82 W/m² blue ( 420 nm - 490 nm) 141 µW/cm² = 1.41 W/m² green ( 490 nm - 575 nm) 104 µW/cm² = 1.04 W/m² yellow ( 575 nm - 585 nm) 12.1 µW/cm² = 0.121 W/m² orange ( 585 nm - 650 nm) 44.1 µW/cm² = 0.441 W/m² red ( 650 nm - 780 nm) 37.3 µW/cm² = 0.373 W/m² IRA ( 700 nm - 1400 nm) 24.6 µW/cm² = 0.246 W/m² IR2 ( 720 nm - 1100 nm) 19.4 µW/cm² = 0.194 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Erythema 3.31 UV-Index Pyrimidine dimerization of DNA 17.6 µW/cm² Photoceratitis 4.74 µW/cm² Photoconjunctivitis 0.85 µW/cm² DNA Damage 1.34 Vitamin D3 10.9 µW/cm² Photosynthesis 263 µW/cm² Luminosity 851 lx Human L-Cone 123 µW/cm² Human M-Cone 115 µW/cm² Human S-Cone 121 µW/cm² CIE X 115 µW/cm² CIE Y 117 µW/cm² CIE Z 220 µW/cm² PAR 1680000 mol photons Extinction preD3 62.1 e-3*m²/mol Extinction Tachysterol 214 e-3*m²/mol Exctincition PreD3 35200 m²/mol Extinction Lumisterol 23.2 m²/mol Exctincition Tachysterol 302000 m²/mol Extinction 7DHC 27.2 m²/mol L-Cone 97 µW/cm² M-Cone 135 µW/cm² S-Cone 218 µW/cm² U-Cone 186 µW/cm² UVR - ICNIRP 2004 3.7 Rel Biol Eff Melatonin Supression 158 µW/cm² Blue Light Hazard 138 µW/cm² (162 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 11.8 µW/cm² Lumen Reptil 1290 "pseudo-lx" Vitamin D3 Degradation 9.22 µW/cm² Actinic UV 3.66 µW/cm² (43.1 mW/klm) Exctincition Lumisterol 28200 m²/mol Exctincition 7DHC 31900 m²/mol Exctincition Toxisterols 7290 m²/mol
Solarmeter 6.2 (UVB, pre 2010) 50.8 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 3.23 Leybold UVB 35.8 µW/cm² Leybold UVA 148 µW/cm² Leybold UVC 0.572 µW/cm² DeltaOhm UVB 83.1 µW/cm² DeltaOhm UVC 10.8 µW/cm² Vernier UVB 15 µW/cm² Vernier UVA 136 µW/cm² Gröbel UVA 179 µW/cm² Gröbel UVB 21.3 µW/cm² Gröbel UVC 0.603 µW/cm² Luxmeter 892 lx Solarmeter 6.4 (D3) 10.1 IU/min UVX-31 94.7 µW/cm² IL UVB 0.023 µW/cm² IL UVA 167 µW/cm² Solarmeter 6.5 (UVI, post 2010) 2.4 UV-Index Solarmeter 6.2 (UVB, post 2010) 31.8 µW/cm² (Solarmeter Ratio = 13.3) Solarmeter AlGaN 6.5 UVI sensor 24.6 UV Index GenUV 7.1 UV-Index 1.36 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 4.83 W/m² Solarmeter 4.0 (UVA) 2.24 mW/cm² LS122 (manuf.) 0.00761 W/m² ISM400 (first guess) 2.64 W/m² LS122 (assumption) 0.109 W/m² ISM400_new 2.13 W/m² Solarmeter 10.0 (Global Power) (assumption) 3.98 W/m²