Spectrum 539: BWWT4 Edit
DeleteMeasurement
| Brand |
Philips Koninklijke Philips Electronics N.V. http://www.philips.com/ |
|---|---|
| Lamp Product |
Master TLD 90 Graphica 965 58W Cool Daylight 6500K tube |
| Lamp ID |
BWWT4 (04/2017) |
| Spectrometer | USB2000+ (2) |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 10 cm |
| Age | 1 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Frances Baines
18/Apr/2017 ; updated:
Frances Baines
18/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 | ( 0.29 ; 0.29 ) | ( 0.43 ; 0.46 ) | ( 0.24 ; 0.33 ; 0.35 ) |
| CCT | 8900 Kelvin | 4600 Kelvin | 5600 Kelvin |
| distance | 0.12 | 0.11 | |
| 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) 899 µW/cm² = 8.99 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) 899 µW/cm² = 8.99 W/m² UVB (EU) ( 280 nm - 315 nm) 1.73 µW/cm² = 0.0173 W/m² UVB (US) ( 280 nm - 320 nm) 1.73 µW/cm² = 0.0173 W/m² UVA+B ( 280 nm - 380 nm) 13.5 µW/cm² = 0.135 W/m² Solar UVB ( 290 nm - 315 nm) 1.73 µW/cm² = 0.0173 W/m² UVA D3 regulating ( 315 nm - 335 nm) 0.202 µW/cm² = 0.00202 W/m² UVA (EU) ( 315 nm - 380 nm) 11.8 µW/cm² = 0.118 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 0.201 µW/cm² = 0.00201 W/m² UVA (US) ( 320 nm - 380 nm) 11.8 µW/cm² = 0.118 W/m² UVA1 (variant) ( 335 nm - 380 nm) 11.6 µW/cm² = 0.116 W/m² UVA1 (medical) ( 340 nm - 400 nm) 21.8 µW/cm² = 0.218 W/m² vis. UVA ( 350 nm - 380 nm) 11.6 µW/cm² = 0.116 W/m² VIS Rep3 ( 350 nm - 600 nm) 690 µW/cm² = 6.9 W/m² VIS Rep4 ( 350 nm - 700 nm) 878 µW/cm² = 8.78 W/m² purple ( 380 nm - 420 nm) 53.9 µW/cm² = 0.539 W/m² VIS ( 380 nm - 780 nm) 885 µW/cm² = 8.85 W/m² VIS2 ( 400 nm - 680 nm) 842 µW/cm² = 8.42 W/m² PAR ( 400 nm - 700 nm) 856 µW/cm² = 8.56 W/m² tmp ( 400 nm - 1100 nm) 875 µW/cm² = 8.75 W/m² blue ( 420 nm - 490 nm) 296 µW/cm² = 2.96 W/m² green ( 490 nm - 575 nm) 262 µW/cm² = 2.62 W/m² yellow ( 575 nm - 585 nm) 29 µW/cm² = 0.29 W/m² orange ( 585 nm - 650 nm) 168 µW/cm² = 1.68 W/m² red ( 650 nm - 780 nm) 75.9 µW/cm² = 0.759 W/m² IRA ( 700 nm - 1400 nm) 18.6 µW/cm² = 0.186 W/m² IR2 ( 720 nm - 1100 nm) 10.4 µW/cm² = 0.104 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 0.0291 UV-Index Pyrimidine dimerization of DNA 0.498 µW/cm² Photoceratitis 0.0781 µW/cm² Photoconjunctivitis 0 µW/cm² DNA Damage 0.000575 Vitamin D3 0.144 µW/cm² Photosynthesis 615 µW/cm² Luminosity 2250 lx Human L-Cone 331 µW/cm² Human M-Cone 290 µW/cm² Human S-Cone 235 µW/cm² CIE X 307 µW/cm² CIE Y 309 µW/cm² CIE Z 443 µW/cm² PAR 3960000 mol photons Extinction preD3 1.46 e-3*m²/mol Extinction Tachysterol 4.86 e-3*m²/mol Exctincition PreD3 622 m²/mol Extinction Lumisterol 0.0262 m²/mol Exctincition Tachysterol 6110 m²/mol Extinction 7DHC 0 m²/mol L-Cone 272 µW/cm² M-Cone 366 µW/cm² S-Cone 387 µW/cm² U-Cone 93 µW/cm² UVR - ICNIRP 2004 0.0118 Rel Biol Eff Melatonin Supression 339 µW/cm² Blue Light Hazard 260 µW/cm² (116 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 0.14 µW/cm² Lumen Reptil 2570 "pseudo-lx" Vitamin D3 Degradation 0.271 µW/cm² Actinic UV 0.0118 µW/cm² (0.0527 mW/klm) Exctincition Lumisterol 129 m²/mol Exctincition 7DHC 34.3 m²/mol Exctincition Toxisterols 86.6 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 1.7 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 0.0355 Leybold UVB 1.38 µW/cm² Leybold UVA 8.87 µW/cm² Leybold UVC 0 µW/cm² DeltaOhm UVB 1.67 µW/cm² DeltaOhm UVC 0.249 µW/cm² Vernier UVB 0.426 µW/cm² Vernier UVA 4.05 µW/cm² Gröbel UVA 10.1 µW/cm² Gröbel UVB 0.668 µW/cm² Gröbel UVC -0.000852 µW/cm² Luxmeter 2300 lx Solarmeter 6.4 (D3) 0.111 IU/min UVX-31 2.1 µW/cm² IL UVB 0.000599 µW/cm² IL UVA 11.7 µW/cm² Solarmeter 6.5 (UVI, post 2010) 0.0384 UV-Index Solarmeter 6.2 (UVB, post 2010) 0.94 µW/cm² (Solarmeter Ratio = 24.4) Solarmeter AlGaN 6.5 UVI sensor 1.03 UV Index GenUV 7.1 UV-Index 0.0556 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 8.89 W/m² Solarmeter 4.0 (UVA) 0.259 mW/cm² LS122 (manuf.) 0 W/m² ISM400 (first guess) 5.87 W/m² LS122 (assumption) 0.272 W/m² ISM400_new 4.66 W/m² Solarmeter 10.0 (Global Power) (assumption) 8.41 W/m²