Spectrum 177: BA19 Edit
DeleteMeasurement
Brand |
Arcadia UK company https://www.arcadiareptile.com/ |
---|---|
Lamp Product |
Arcadia Bird Lamp 18W |
Lamp ID |
BA19 (01/2008) 2.4% UVB T8 |
Spectrometer | USB2000+ |
Ballast | - no ballast or default/unknown ballast - |
Reflector | |
Distance | 10 cm |
Age | 105 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 | ( 0.32 ; 0.31 ) | ( 0.4 ; 0.48 ) | ( 0.29 ; 0.28 ; 0.34 ) |
CCT | 6500 Kelvin | 5100 Kelvin | 5100 Kelvin |
distance | 0.14 | 0.1 | |
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) 764 µW/cm² = 7.64 W/m² UVC ( 0 nm - 280 nm) 0.0311 µW/cm² = 0.000311 W/m² non-terrestrial ( 0 nm - 290 nm) 0.0311 µW/cm² = 0.000311 W/m² total2 ( 250 nm - 880 nm) 764 µW/cm² = 7.64 W/m² UVB (EU) ( 280 nm - 315 nm) 4.03 µW/cm² = 0.0403 W/m² UVB (US) ( 280 nm - 320 nm) 6.89 µW/cm² = 0.0689 W/m² UVA+B ( 280 nm - 380 nm) 49.4 µW/cm² = 0.494 W/m² Solar UVB ( 290 nm - 315 nm) 4.03 µW/cm² = 0.0403 W/m² UVA D3 regulating ( 315 nm - 335 nm) 14 µW/cm² = 0.14 W/m² UVA (EU) ( 315 nm - 380 nm) 45.4 µW/cm² = 0.454 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 15.8 µW/cm² = 0.158 W/m² UVA (US) ( 320 nm - 380 nm) 42.5 µW/cm² = 0.425 W/m² UVA1 (variant) ( 335 nm - 380 nm) 31.4 µW/cm² = 0.314 W/m² UVA1 (medical) ( 340 nm - 400 nm) 32.8 µW/cm² = 0.328 W/m² vis. UVA ( 350 nm - 380 nm) 18.6 µW/cm² = 0.186 W/m² VIS Rep3 ( 350 nm - 600 nm) 571 µW/cm² = 5.71 W/m² VIS Rep4 ( 350 nm - 700 nm) 718 µW/cm² = 7.18 W/m² purple ( 380 nm - 420 nm) 38.4 µW/cm² = 0.384 W/m² VIS ( 380 nm - 780 nm) 711 µW/cm² = 7.11 W/m² VIS2 ( 400 nm - 680 nm) 688 µW/cm² = 6.88 W/m² PAR ( 400 nm - 700 nm) 693 µW/cm² = 6.93 W/m² tmp ( 400 nm - 1100 nm) 708 µW/cm² = 7.08 W/m² blue ( 420 nm - 490 nm) 234 µW/cm² = 2.34 W/m² green ( 490 nm - 575 nm) 222 µW/cm² = 2.22 W/m² yellow ( 575 nm - 585 nm) 23.2 µW/cm² = 0.232 W/m² orange ( 585 nm - 650 nm) 165 µW/cm² = 1.65 W/m² red ( 650 nm - 780 nm) 28.6 µW/cm² = 0.286 W/m² IRA ( 700 nm - 1400 nm) 15.1 µW/cm² = 0.151 W/m² IR2 ( 720 nm - 1100 nm) 4.91 µW/cm² = 0.0491 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Erythema 0.132 UV-Index Pyrimidine dimerization of DNA 2.02 µW/cm² Photoceratitis 0.225 µW/cm² Photoconjunctivitis 0.0292 µW/cm² DNA Damage 0.0345 Vitamin D3 0.511 µW/cm² Photosynthesis 481 µW/cm² Luminosity 2140 lx Human L-Cone 319 µW/cm² Human M-Cone 267 µW/cm² Human S-Cone 187 µW/cm² CIE X 297 µW/cm² CIE Y 296 µW/cm² CIE Z 349 µW/cm² PAR 3180000 mol photons Extinction preD3 6.39 e-3*m²/mol Extinction Tachysterol 22.7 e-3*m²/mol Exctincition PreD3 3290 m²/mol Extinction Lumisterol 0.33 m²/mol Exctincition Tachysterol 35300 m²/mol Extinction 7DHC 0.192 m²/mol L-Cone 265 µW/cm² M-Cone 261 µW/cm² S-Cone 316 µW/cm² U-Cone 76.9 µW/cm² UVR - ICNIRP 2004 0.07 Rel Biol Eff Melatonin Supression 256 µW/cm² Blue Light Hazard 207 µW/cm² (97 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 0.526 µW/cm² Lumen Reptil 2170 "pseudo-lx" Vitamin D3 Degradation 1.22 µW/cm² Actinic UV 0.0706 µW/cm² (0.33 mW/klm) Exctincition Lumisterol 668 m²/mol Exctincition 7DHC 282 m²/mol Exctincition Toxisterols 933 m²/mol
Solarmeter 6.2 (UVB, pre 2010) 8.41 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 0.152 Leybold UVB 5.81 µW/cm² Leybold UVA 31.3 µW/cm² Leybold UVC 0.0296 µW/cm² DeltaOhm UVB 17.1 µW/cm² DeltaOhm UVC 1.9 µW/cm² Vernier UVB 1.31 µW/cm² Vernier UVA 29.4 µW/cm² Gröbel UVA 38.5 µW/cm² Gröbel UVB 2.5 µW/cm² Gröbel UVC 0.0243 µW/cm² Luxmeter 2180 lx Solarmeter 6.4 (D3) 0.475 IU/min UVX-31 19 µW/cm² IL UVB 0.00358 µW/cm² IL UVA 35.8 µW/cm² Solarmeter 6.5 (UVI, post 2010) 0.148 UV-Index Solarmeter 6.2 (UVB, post 2010) 5.98 µW/cm² (Solarmeter Ratio = 40.5) Solarmeter AlGaN 6.5 UVI sensor 3.03 UV Index GenUV 7.1 UV-Index 0.188 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 7.34 W/m² Solarmeter 4.0 (UVA) 0.513 mW/cm² LS122 (manuf.) 0.00267 W/m² ISM400 (first guess) 4.7 W/m² LS122 (assumption) 0.232 W/m² ISM400_new 3.69 W/m² Solarmeter 10.0 (Global Power) (assumption) 6.9 W/m²