Spectrum 538: BWWT3 Edit
DeleteMeasurement
| Brand |
Philips Koninklijke Philips Electronics N.V. http://www.philips.com/ |
|---|---|
| Lamp Product |
Master TLD Super 80 Cool White 840 58W 4000K T8 tube |
| Lamp ID |
BWWT3 (04/2017) |
| Spectrometer | USB2000+ (2) |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 86 cm |
| Age | 1 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Frances Baines
17/Apr/2017 ; updated:
Frances Baines
17/Apr/2017
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 | ( 0.37 ; 0.37 ) | ( 0.43 ; 0.47 ) | ( 0.4 ; 0.26 ; 0.28 ) |
| CCT | 4200 Kelvin | 4600 Kelvin | 3700 Kelvin |
| distance | 0.13 | 0.092 | |
| 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) 200 µW/cm² = 2 W/m² UVC ( 0 nm - 280 nm) 0 µW/cm² = 0 W/m² non-terrestrial ( 0 nm - 290 nm) 0.0203 µW/cm² = 0.000203 W/m² total2 ( 250 nm - 880 nm) 200 µW/cm² = 2 W/m² UVB (EU) ( 280 nm - 315 nm) 0.879 µW/cm² = 0.00879 W/m² UVB (US) ( 280 nm - 320 nm) 1.14 µW/cm² = 0.0114 W/m² UVA+B ( 280 nm - 380 nm) 5.78 µW/cm² = 0.0578 W/m² Solar UVB ( 290 nm - 315 nm) 0.859 µW/cm² = 0.00859 W/m² UVA D3 regulating ( 315 nm - 335 nm) 1.2 µW/cm² = 0.012 W/m² UVA (EU) ( 315 nm - 380 nm) 4.9 µW/cm² = 0.049 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 1.29 µW/cm² = 0.0129 W/m² UVA (US) ( 320 nm - 380 nm) 4.64 µW/cm² = 0.0464 W/m² UVA1 (variant) ( 335 nm - 380 nm) 3.7 µW/cm² = 0.037 W/m² UVA1 (medical) ( 340 nm - 400 nm) 3.87 µW/cm² = 0.0387 W/m² vis. UVA ( 350 nm - 380 nm) 2.73 µW/cm² = 0.0273 W/m² VIS Rep3 ( 350 nm - 600 nm) 134 µW/cm² = 1.34 W/m² VIS Rep4 ( 350 nm - 700 nm) 187 µW/cm² = 1.87 W/m² purple ( 380 nm - 420 nm) 6.19 µW/cm² = 0.0619 W/m² VIS ( 380 nm - 780 nm) 193 µW/cm² = 1.93 W/m² PAR ( 400 nm - 700 nm) 184 µW/cm² = 1.84 W/m² blue ( 420 nm - 490 nm) 44.7 µW/cm² = 0.447 W/m² green ( 490 nm - 575 nm) 60.9 µW/cm² = 0.609 W/m² yellow ( 575 nm - 585 nm) 7.32 µW/cm² = 0.0732 W/m² orange ( 585 nm - 650 nm) 59.4 µW/cm² = 0.594 W/m² red ( 650 nm - 780 nm) 14.6 µW/cm² = 0.146 W/m² IRA ( 700 nm - 1400 nm) 9.73 µW/cm² = 0.0973 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 0.046 UV-Index Pyrimidine dimerization of DNA 0.376 µW/cm² Photoceratitis 0.0823 µW/cm² Photoconjunctivitis 0.00597 µW/cm² DNA Damage 0.0149 Vitamin D3 0.167 µW/cm² Photosynthesis 121 µW/cm² Luminosity 654 lx Human L-Cone 99.8 µW/cm² Human M-Cone 77.4 µW/cm² Human S-Cone 35.3 µW/cm² CIE X 92.4 µW/cm² CIE Y 91.1 µW/cm² CIE Z 66 µW/cm² PAR 864000 mol photons Extinction preD3 1.25 e-3*m²/mol Extinction Tachysterol 4.46 e-3*m²/mol Exctincition PreD3 636 m²/mol Extinction Lumisterol 0.295 m²/mol Exctincition Tachysterol 6160 m²/mol Extinction 7DHC 0.352 m²/mol L-Cone 85.9 µW/cm² M-Cone 55.8 µW/cm² S-Cone 60.3 µW/cm² U-Cone 12.5 µW/cm² UVR - ICNIRP 2004 0.0474 Rel Biol Eff Melatonin Supression 48.9 µW/cm² Blue Light Hazard 39.4 µW/cm² (60.2 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 0.174 µW/cm² Lumen Reptil 541 "pseudo-lx" Vitamin D3 Degradation 0.216 µW/cm² Actinic UV 0.047 µW/cm² (0.719 mW/klm) Exctincition Lumisterol 401 m²/mol Exctincition 7DHC 439 m²/mol Exctincition Toxisterols 93 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 1.29 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 0.0496 Leybold UVB 0.936 µW/cm² Leybold UVA 3.34 µW/cm² Leybold UVC 0.000122 µW/cm² DeltaOhm UVB 1.91 µW/cm² DeltaOhm UVC 0.245 µW/cm² Vernier UVB 0.304 µW/cm² Vernier UVA 2.91 µW/cm² Gröbel UVA 4.24 µW/cm² Gröbel UVB 0.483 µW/cm² Gröbel UVC 0.00109 µW/cm² Solarmeter 6.4 (D3) 0.155 IU/min UVX-31 2.14 µW/cm² IL UVB 0.000522 µW/cm² IL UVA 4.06 µW/cm² Solarmeter 6.5 (UVI, post 2010) 0.0394 UV-Index Solarmeter 6.2 (UVB, post 2010) 0.809 µW/cm² (Solarmeter Ratio = 20.5) Solarmeter AlGaN 6.5 UVI sensor 0.619 UV Index GenUV 7.1 UV-Index 0.0345 UV-Index Solarmeter 10.0 (Global Power) 2.12 W/m² Solarmeter 4.0 (UVA) 0.0605 mW/cm² LS122 0 W/m² ISM400 1.51 W/m²