Spectrum 491: BAH6 Edit
DeleteMeasurement
| Brand |
S&P Lighting GbR German company, founded 2010 by Sven Haferland and Peter Errmann focus on LED products, also for reptiles www.sp-lighting.de |
|---|---|
| Lamp Product |
PAR38 prototype PAR38 5000K prototype |
| Lamp ID |
BAH6 (02/2014) PAR38 5000K metal halide prototype |
| Spectrometer | USB2000+ (2) |
| Ballast | Osram Powertronic PTi 70 220-240I |
| Reflector | |
| Distance | 30 cm |
| Age | 105 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Frances Baines
25/Feb/2014 ; updated:
Frances Baines
25/Feb/2014
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 ; 0.34 ) | ( 0.22 ; 0.4 ) | ( 0.24 ; 0.17 ; 0.3 ) |
| CCT | 5900 Kelvin | 13000 Kelvin | 7600 Kelvin |
| distance | 0.072 | 0.09 | |
| 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) 59200 µW/cm² = 592 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) 59200 µW/cm² = 592 W/m² UVB (EU) ( 280 nm - 315 nm) 102 µW/cm² = 1.02 W/m² UVB (US) ( 280 nm - 320 nm) 141 µW/cm² = 1.41 W/m² UVA+B ( 280 nm - 380 nm) 7390 µW/cm² = 73.9 W/m² Solar UVB ( 290 nm - 315 nm) 102 µW/cm² = 1.02 W/m² UVA D3 regulating ( 315 nm - 335 nm) 337 µW/cm² = 3.37 W/m² UVA (EU) ( 315 nm - 380 nm) 7290 µW/cm² = 72.9 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 464 µW/cm² = 4.64 W/m² UVA (US) ( 320 nm - 380 nm) 7250 µW/cm² = 72.5 W/m² UVA1 (variant) ( 335 nm - 380 nm) 6950 µW/cm² = 69.5 W/m² UVA1 (medical) ( 340 nm - 400 nm) 9670 µW/cm² = 96.7 W/m² vis. UVA ( 350 nm - 380 nm) 6310 µW/cm² = 63.1 W/m² VIS Rep3 ( 350 nm - 600 nm) 43600 µW/cm² = 436 W/m² VIS Rep4 ( 350 nm - 700 nm) 51000 µW/cm² = 510 W/m² purple ( 380 nm - 420 nm) 7410 µW/cm² = 74.1 W/m² VIS ( 380 nm - 780 nm) 47200 µW/cm² = 472 W/m² PAR ( 400 nm - 700 nm) 41800 µW/cm² = 418 W/m² blue ( 420 nm - 490 nm) 11400 µW/cm² = 114 W/m² green ( 490 nm - 575 nm) 12100 µW/cm² = 121 W/m² yellow ( 575 nm - 585 nm) 2240 µW/cm² = 22.4 W/m² orange ( 585 nm - 650 nm) 8420 µW/cm² = 84.2 W/m² red ( 650 nm - 780 nm) 5630 µW/cm² = 56.3 W/m² IRA ( 700 nm - 1400 nm) 7150 µW/cm² = 71.5 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 4.46 UV-Index Pyrimidine dimerization of DNA 46.7 µW/cm² Photoceratitis 5.69 µW/cm² Photoconjunctivitis 0.0367 µW/cm² DNA Damage 0.155 Vitamin D3 13.2 µW/cm² Photosynthesis 28700 µW/cm² Luminosity 126000 lx Human L-Cone 18800 µW/cm² Human M-Cone 15800 µW/cm² Human S-Cone 10300 µW/cm² CIE X 16800 µW/cm² CIE Y 17600 µW/cm² CIE Z 17600 µW/cm² PAR 195000000 mol photons Extinction preD3 137 e-3*m²/mol Extinction Tachysterol 498 e-3*m²/mol Exctincition PreD3 78600 m²/mol Extinction Lumisterol 6.91 m²/mol Exctincition Tachysterol 944000 m²/mol Extinction 7DHC 4.24 m²/mol L-Cone 15700 µW/cm² M-Cone 11000 µW/cm² S-Cone 19900 µW/cm² U-Cone 19300 µW/cm² UVR - ICNIRP 2004 2.72 Rel Biol Eff Melatonin Supression 13100 µW/cm² Blue Light Hazard 12800 µW/cm² (101 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 13.6 µW/cm² Lumen Reptil 143000 "pseudo-lx" Vitamin D3 Degradation 27.2 µW/cm² Actinic UV 2.7 µW/cm² (0.214 mW/klm) Exctincition Lumisterol 15400 m²/mol Exctincition 7DHC 7300 m²/mol Exctincition Toxisterols 22300 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 213 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 4.38 Leybold UVB 128 µW/cm² Leybold UVA 5480 µW/cm² Leybold UVC 0.000986 µW/cm² DeltaOhm UVB 439 µW/cm² DeltaOhm UVC 38.8 µW/cm² Vernier UVB 31.1 µW/cm² Vernier UVA 3000 µW/cm² Gröbel UVA 6010 µW/cm² Gröbel UVB 60.5 µW/cm² Gröbel UVC -0.0549 µW/cm² Solarmeter 6.4 (D3) 13.7 IU/min UVX-31 762 µW/cm² IL UVB 0.108 µW/cm² IL UVA 6780 µW/cm² Solarmeter 6.5 (UVI, post 2010) 3.78 UV-Index Solarmeter 6.2 (UVB, post 2010) 129 µW/cm² (Solarmeter Ratio = 34.1) Solarmeter AlGaN 6.5 UVI sensor 71.4 UV Index GenUV 7.1 UV-Index 5.66 UV-Index Solarmeter 10.0 (Global Power) 581 W/m² Solarmeter 4.0 (UVA) 107 mW/cm² LS122 6.48 W/m² ISM400 431 W/m²