Spectrum 145: BAC4 Edit
DeleteMeasurement
| Brand |
Arcadia UK company https://www.arcadiareptile.com/ |
|---|---|
| Lamp Product |
Arcadia D3 Compact 23W |
| Lamp ID |
BAC4 (01/2008) |
| Spectrometer | USB 2000 |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 10 cm |
| Age | 1 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Sarina Wunderlich
28/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 ; 0.31 ) | ( 0.34 ; 0.46 ) | ( 0.25 ; 0.25 ; 0.34 ) |
| CCT | 7400 Kelvin | 6200 Kelvin | 5900 Kelvin |
| distance | 0.11 | 0.083 | |
| 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) 2140 µW/cm² = 21.4 W/m² UVC ( 0 nm - 280 nm) 5.01 µW/cm² = 0.0501 W/m² non-terrestrial ( 0 nm - 290 nm) 6.46 µW/cm² = 0.0646 W/m² total2 ( 250 nm - 880 nm) 2140 µW/cm² = 21.4 W/m² UVB (EU) ( 280 nm - 315 nm) 79.9 µW/cm² = 0.799 W/m² UVB (US) ( 280 nm - 320 nm) 138 µW/cm² = 1.38 W/m² UVA+B ( 280 nm - 380 nm) 693 µW/cm² = 6.93 W/m² Solar UVB ( 290 nm - 315 nm) 78.4 µW/cm² = 0.784 W/m² UVA D3 regulating ( 315 nm - 335 nm) 265 µW/cm² = 2.65 W/m² UVA (EU) ( 315 nm - 380 nm) 613 µW/cm² = 6.13 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 287 µW/cm² = 2.87 W/m² UVA (US) ( 320 nm - 380 nm) 555 µW/cm² = 5.55 W/m² UVA1 (variant) ( 335 nm - 380 nm) 348 µW/cm² = 3.48 W/m² UVA1 (medical) ( 340 nm - 400 nm) 281 µW/cm² = 2.81 W/m² vis. UVA ( 350 nm - 380 nm) 139 µW/cm² = 1.39 W/m² VIS Rep3 ( 350 nm - 600 nm) 1190 µW/cm² = 11.9 W/m² VIS Rep4 ( 350 nm - 700 nm) 1470 µW/cm² = 14.7 W/m² purple ( 380 nm - 420 nm) 110 µW/cm² = 1.1 W/m² VIS ( 380 nm - 780 nm) 1400 µW/cm² = 14 W/m² VIS2 ( 400 nm - 680 nm) 1290 µW/cm² = 12.9 W/m² PAR ( 400 nm - 700 nm) 1320 µW/cm² = 13.2 W/m² tmp ( 400 nm - 1100 nm) 1430 µW/cm² = 14.3 W/m² blue ( 420 nm - 490 nm) 409 µW/cm² = 4.09 W/m² green ( 490 nm - 575 nm) 411 µW/cm² = 4.11 W/m² yellow ( 575 nm - 585 nm) 71.8 µW/cm² = 0.718 W/m² orange ( 585 nm - 650 nm) 234 µW/cm² = 2.34 W/m² red ( 650 nm - 780 nm) 166 µW/cm² = 1.66 W/m² IRA ( 700 nm - 1400 nm) 110 µW/cm² = 1.1 W/m² IR2 ( 720 nm - 1100 nm) 83.5 µW/cm² = 0.835 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 6.87 UV-Index Pyrimidine dimerization of DNA 49.3 µW/cm² Photoceratitis 9.39 µW/cm² Photoconjunctivitis 4.67 µW/cm² DNA Damage 5.64 Vitamin D3 20.2 µW/cm² Photosynthesis 921 µW/cm² Luminosity 3740 lx Human L-Cone 552 µW/cm² Human M-Cone 480 µW/cm² Human S-Cone 344 µW/cm² CIE X 498 µW/cm² CIE Y 520 µW/cm² CIE Z 636 µW/cm² PAR 6380000 mol photons Extinction preD3 191 e-3*m²/mol Extinction Tachysterol 615 e-3*m²/mol Exctincition PreD3 116000 m²/mol Extinction Lumisterol 59.2 m²/mol Exctincition Tachysterol 892000 m²/mol Extinction 7DHC 64.8 m²/mol L-Cone 457 µW/cm² M-Cone 455 µW/cm² S-Cone 612 µW/cm² U-Cone 278 µW/cm² UVR - ICNIRP 2004 8.01 Rel Biol Eff Melatonin Supression 465 µW/cm² Blue Light Hazard 390 µW/cm² (104 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 21.8 µW/cm² Lumen Reptil 4070 "pseudo-lx" Vitamin D3 Degradation 28.3 µW/cm² Actinic UV 7.97 µW/cm² (21.3 mW/klm) Exctincition Lumisterol 70800 m²/mol Exctincition 7DHC 71200 m²/mol Exctincition Toxisterols 34700 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 176 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 6.27 Leybold UVB 119 µW/cm² Leybold UVA 400 µW/cm² Leybold UVC 3.81 µW/cm² DeltaOhm UVB 323 µW/cm² DeltaOhm UVC 41.3 µW/cm² Vernier UVB 36.2 µW/cm² Vernier UVA 451 µW/cm² Gröbel UVA 516 µW/cm² Gröbel UVB 58.3 µW/cm² Gröbel UVC 4.01 µW/cm² Luxmeter 3870 lx Solarmeter 6.4 (D3) 19.6 IU/min UVX-31 351 µW/cm² IL UVB 0.0749 µW/cm² IL UVA 438 µW/cm² Solarmeter 6.5 (UVI, post 2010) 5.27 UV-Index Solarmeter 6.2 (UVB, post 2010) 120 µW/cm² (Solarmeter Ratio = 22.7) Solarmeter AlGaN 6.5 UVI sensor 69.7 UV Index GenUV 7.1 UV-Index 4.17 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 17.7 W/m² Solarmeter 4.0 (UVA) 5.59 mW/cm² LS122 (manuf.) 0.0615 W/m² ISM400 (first guess) 11 W/m² LS122 (assumption) 0.534 W/m² ISM400_new 9.15 W/m² Solarmeter 10.0 (Global Power) (assumption) 15.5 W/m²