Spectrum 138: BM17 Edit
DeleteMeasurement
| Brand |
MegaRay Mac Industries Inc http://www.reptileuv.com/ |
|---|---|
| Lamp Product |
Mega Ray 275W |
| Lamp ID |
BM17 (12/2008) |
| Spectrometer | USB 2000 |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 30 cm |
| Age | 1 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Sarina Wunderlich
20/Mar/2010 ; updated:
Sarina Wunderlich
9/Oct/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 | ( 0.3 ; 0.34 ) | ( 0.11 ; 0.39 ) | ( 0.22 ; 0.088 ; 0.31 ) |
| CCT | 6800 Kelvin | 0 Kelvin | 16000 Kelvin |
| distance | 0 | 0.14 | |
| 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) 46300 µW/cm² = 463 W/m² UVC ( 0 nm - 280 nm) 24.3 µW/cm² = 0.243 W/m² non-terrestrial ( 0 nm - 290 nm) 32.2 µW/cm² = 0.322 W/m² total2 ( 250 nm - 880 nm) 46300 µW/cm² = 463 W/m² UVB (EU) ( 280 nm - 315 nm) 916 µW/cm² = 9.16 W/m² UVB (US) ( 280 nm - 320 nm) 1050 µW/cm² = 10.5 W/m² UVA+B ( 280 nm - 380 nm) 12300 µW/cm² = 123 W/m² Solar UVB ( 290 nm - 315 nm) 908 µW/cm² = 9.08 W/m² UVA D3 regulating ( 315 nm - 335 nm) 790 µW/cm² = 7.9 W/m² UVA (EU) ( 315 nm - 380 nm) 11400 µW/cm² = 114 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 935 µW/cm² = 9.35 W/m² UVA (US) ( 320 nm - 380 nm) 11300 µW/cm² = 113 W/m² UVA1 (variant) ( 335 nm - 380 nm) 10600 µW/cm² = 106 W/m² UVA1 (medical) ( 340 nm - 400 nm) 10800 µW/cm² = 108 W/m² vis. UVA ( 350 nm - 380 nm) 10000 µW/cm² = 100 W/m² VIS Rep3 ( 350 nm - 600 nm) 39300 µW/cm² = 393 W/m² VIS Rep4 ( 350 nm - 700 nm) 41000 µW/cm² = 410 W/m² purple ( 380 nm - 420 nm) 4730 µW/cm² = 47.3 W/m² VIS ( 380 nm - 780 nm) 32300 µW/cm² = 323 W/m² PAR ( 400 nm - 700 nm) 30400 µW/cm² = 304 W/m² blue ( 420 nm - 490 nm) 8980 µW/cm² = 89.8 W/m² green ( 490 nm - 575 nm) 8720 µW/cm² = 87.2 W/m² yellow ( 575 nm - 585 nm) 6580 µW/cm² = 65.8 W/m² orange ( 585 nm - 650 nm) 1050 µW/cm² = 10.5 W/m² red ( 650 nm - 780 nm) 2210 µW/cm² = 22.1 W/m² IRA ( 700 nm - 1400 nm) 3060 µW/cm² = 30.6 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 51.6 UV-Index Pyrimidine dimerization of DNA 350 µW/cm² Photoceratitis 79.8 µW/cm² Photoconjunctivitis 23.1 µW/cm² DNA Damage 29.7 Vitamin D3 165 µW/cm² Photosynthesis 20000 µW/cm² Luminosity 104000 lx Human L-Cone 15300 µW/cm² Human M-Cone 13600 µW/cm² Human S-Cone 8810 µW/cm² CIE X 13200 µW/cm² CIE Y 14800 µW/cm² CIE Z 15400 µW/cm² PAR 155000000 mol photons Extinction preD3 1270 e-3*m²/mol Extinction Tachysterol 4120 e-3*m²/mol Exctincition PreD3 721000 m²/mol Extinction Lumisterol 365 m²/mol Exctincition Tachysterol 5550000 m²/mol Extinction 7DHC 406 m²/mol L-Cone 12800 µW/cm² M-Cone 5200 µW/cm² S-Cone 18200 µW/cm² U-Cone 22700 µW/cm² UVR - ICNIRP 2004 55.9 Rel Biol Eff Melatonin Supression 9810 µW/cm² Blue Light Hazard 10100 µW/cm² (96.9 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 171 µW/cm² Lumen Reptil 120000 "pseudo-lx" Vitamin D3 Degradation 193 µW/cm² Actinic UV 55.2 µW/cm² (5.28 mW/klm) Exctincition Lumisterol 458000 m²/mol Exctincition 7DHC 463000 m²/mol Exctincition Toxisterols 170000 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 1130 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 48.3 Leybold UVB 839 µW/cm² Leybold UVA 7760 µW/cm² Leybold UVC 18.1 µW/cm² DeltaOhm UVB 1490 µW/cm² DeltaOhm UVC 203 µW/cm² Vernier UVB 287 µW/cm² Vernier UVA 4790 µW/cm² Gröbel UVA 9660 µW/cm² Gröbel UVB 454 µW/cm² Gröbel UVC 19.2 µW/cm² Solarmeter 6.4 (D3) 151 IU/min UVX-31 1900 µW/cm² IL UVB 0.462 µW/cm² IL UVA 10400 µW/cm² Solarmeter 6.5 (UVI, post 2010) 39.4 UV-Index Solarmeter 6.2 (UVB, post 2010) 645 µW/cm² (Solarmeter Ratio = 16.4) Solarmeter AlGaN 6.5 UVI sensor 592 UV Index GenUV 7.1 UV-Index 33.9 UV-Index Solarmeter 10.0 (Global Power) 393 W/m² Solarmeter 4.0 (UVA) 140 mW/cm² LS122 1.92 W/m² ISM400 245 W/m²