Spectrum 324: BRO1 Edit
DeleteMeasurement
| Brand |
Reptile One http://www.reptileone.com. |
|---|---|
| Lamp Product |
UVB 10.0 T8 18W |
| Lamp ID |
BRO1 (08/2009) |
| Spectrometer | USB2000+ (2) |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 10 cm |
| Age | 1 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Sarina Wunderlich
3/Jul/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.
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 ) | ( 0.21 ; 0.38 ) | ( 0.18 ; 0.17 ; 0.31 ) |
| CCT | 8800 Kelvin | 16000 Kelvin | 12000 Kelvin |
| distance | 0.055 | 0.057 | |
| 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) 1010 µW/cm² = 10.1 W/m² UVC ( 0 nm - 280 nm) 2.31 µW/cm² = 0.0231 W/m² non-terrestrial ( 0 nm - 290 nm) 3.4 µW/cm² = 0.034 W/m² total2 ( 250 nm - 880 nm) 1010 µW/cm² = 10.1 W/m² UVB (EU) ( 280 nm - 315 nm) 68.8 µW/cm² = 0.688 W/m² UVB (US) ( 280 nm - 320 nm) 98.8 µW/cm² = 0.988 W/m² UVA+B ( 280 nm - 380 nm) 461 µW/cm² = 4.61 W/m² Solar UVB ( 290 nm - 315 nm) 67.7 µW/cm² = 0.677 W/m² UVA D3 regulating ( 315 nm - 335 nm) 139 µW/cm² = 1.39 W/m² UVA (EU) ( 315 nm - 380 nm) 393 µW/cm² = 3.93 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 149 µW/cm² = 1.49 W/m² UVA (US) ( 320 nm - 380 nm) 362 µW/cm² = 3.62 W/m² UVA1 (variant) ( 335 nm - 380 nm) 254 µW/cm² = 2.54 W/m² UVA1 (medical) ( 340 nm - 400 nm) 245 µW/cm² = 2.45 W/m² vis. UVA ( 350 nm - 380 nm) 142 µW/cm² = 1.42 W/m² VIS Rep3 ( 350 nm - 600 nm) 544 µW/cm² = 5.44 W/m² VIS Rep4 ( 350 nm - 700 nm) 651 µW/cm² = 6.51 W/m² purple ( 380 nm - 420 nm) 77.7 µW/cm² = 0.777 W/m² VIS ( 380 nm - 780 nm) 536 µW/cm² = 5.36 W/m² VIS2 ( 400 nm - 680 nm) 463 µW/cm² = 4.63 W/m² PAR ( 400 nm - 700 nm) 477 µW/cm² = 4.77 W/m² tmp ( 400 nm - 1100 nm) 515 µW/cm² = 5.15 W/m² blue ( 420 nm - 490 nm) 154 µW/cm² = 1.54 W/m² green ( 490 nm - 575 nm) 131 µW/cm² = 1.31 W/m² yellow ( 575 nm - 585 nm) 19.6 µW/cm² = 0.196 W/m² orange ( 585 nm - 650 nm) 82.4 µW/cm² = 0.824 W/m² red ( 650 nm - 780 nm) 71.2 µW/cm² = 0.712 W/m² IRA ( 700 nm - 1400 nm) 37.7 µW/cm² = 0.377 W/m² IR2 ( 720 nm - 1100 nm) 27.6 µW/cm² = 0.276 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 6.37 UV-Index Pyrimidine dimerization of DNA 40.2 µW/cm² Photoceratitis 9.09 µW/cm² Photoconjunctivitis 2.32 µW/cm² DNA Damage 3.22 Vitamin D3 21.2 µW/cm² Photosynthesis 343 µW/cm² Luminosity 1200 lx Human L-Cone 178 µW/cm² Human M-Cone 153 µW/cm² Human S-Cone 136 µW/cm² CIE X 172 µW/cm² CIE Y 167 µW/cm² CIE Z 246 µW/cm² PAR 2320000 mol photons Extinction preD3 141 e-3*m²/mol Extinction Tachysterol 470 e-3*m²/mol Exctincition PreD3 79500 m²/mol Extinction Lumisterol 46.2 m²/mol Exctincition Tachysterol 654000 m²/mol Extinction 7DHC 51.7 m²/mol L-Cone 149 µW/cm² M-Cone 143 µW/cm² S-Cone 256 µW/cm² U-Cone 282 µW/cm² UVR - ICNIRP 2004 7.02 Rel Biol Eff Melatonin Supression 174 µW/cm² Blue Light Hazard 159 µW/cm² (132 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 23 µW/cm² Lumen Reptil 1680 "pseudo-lx" Vitamin D3 Degradation 21.1 µW/cm² Actinic UV 6.95 µW/cm² (57.7 mW/klm) Exctincition Lumisterol 56200 m²/mol Exctincition 7DHC 59500 m²/mol Exctincition Toxisterols 18600 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 121 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 6.31 Leybold UVB 85.7 µW/cm² Leybold UVA 262 µW/cm² Leybold UVC 1.72 µW/cm² DeltaOhm UVB 191 µW/cm² DeltaOhm UVC 25.5 µW/cm² Vernier UVB 33.7 µW/cm² Vernier UVA 269 µW/cm² Gröbel UVA 332 µW/cm² Gröbel UVB 47.4 µW/cm² Gröbel UVC 1.82 µW/cm² Luxmeter 1240 lx Solarmeter 6.4 (D3) 19.7 IU/min UVX-31 211 µW/cm² IL UVB 0.0518 µW/cm² IL UVA 299 µW/cm² Solarmeter 6.5 (UVI, post 2010) 4.92 UV-Index Solarmeter 6.2 (UVB, post 2010) 77.1 µW/cm² (Solarmeter Ratio = 15.7) Solarmeter AlGaN 6.5 UVI sensor 57.1 UV Index GenUV 7.1 UV-Index 3.2 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 7.34 W/m² Solarmeter 4.0 (UVA) 3.98 mW/cm² LS122 (manuf.) 0.00788 W/m² ISM400 (first guess) 4.02 W/m² LS122 (assumption) 0.18 W/m² ISM400_new 3.28 W/m² Solarmeter 10.0 (Global Power) (assumption) 5.94 W/m²