Spectrum 146: 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 | 105 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 | ( 0.29 ; 0.3 ) | ( 0.31 ; 0.46 ) | ( 0.23 ; 0.24 ; 0.36 ) |
| CCT | 8700 Kelvin | 7000 Kelvin | 6700 Kelvin |
| distance | 0.12 | 0.093 | |
| 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) 1940 µW/cm² = 19.4 W/m² UVC ( 0 nm - 280 nm) 1.77 µW/cm² = 0.0177 W/m² non-terrestrial ( 0 nm - 290 nm) 2.37 µW/cm² = 0.0237 W/m² total2 ( 250 nm - 880 nm) 1940 µW/cm² = 19.4 W/m² UVB (EU) ( 280 nm - 315 nm) 70.1 µW/cm² = 0.701 W/m² UVB (US) ( 280 nm - 320 nm) 128 µW/cm² = 1.28 W/m² UVA+B ( 280 nm - 380 nm) 728 µW/cm² = 7.28 W/m² Solar UVB ( 290 nm - 315 nm) 69.5 µW/cm² = 0.695 W/m² UVA D3 regulating ( 315 nm - 335 nm) 272 µW/cm² = 2.72 W/m² UVA (EU) ( 315 nm - 380 nm) 658 µW/cm² = 6.58 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 300 µW/cm² = 3 W/m² UVA (US) ( 320 nm - 380 nm) 600 µW/cm² = 6 W/m² UVA1 (variant) ( 335 nm - 380 nm) 386 µW/cm² = 3.86 W/m² UVA1 (medical) ( 340 nm - 400 nm) 311 µW/cm² = 3.11 W/m² vis. UVA ( 350 nm - 380 nm) 156 µW/cm² = 1.56 W/m² VIS Rep3 ( 350 nm - 600 nm) 1090 µW/cm² = 10.9 W/m² VIS Rep4 ( 350 nm - 700 nm) 1300 µW/cm² = 13 W/m² purple ( 380 nm - 420 nm) 108 µW/cm² = 1.08 W/m² VIS ( 380 nm - 780 nm) 1190 µW/cm² = 11.9 W/m² VIS2 ( 400 nm - 680 nm) 1110 µW/cm² = 11.1 W/m² PAR ( 400 nm - 700 nm) 1130 µW/cm² = 11.3 W/m² tmp ( 400 nm - 1100 nm) 1200 µW/cm² = 12 W/m² blue ( 420 nm - 490 nm) 380 µW/cm² = 3.8 W/m² green ( 490 nm - 575 nm) 342 µW/cm² = 3.42 W/m² yellow ( 575 nm - 585 nm) 59.8 µW/cm² = 0.598 W/m² orange ( 585 nm - 650 nm) 181 µW/cm² = 1.81 W/m² red ( 650 nm - 780 nm) 119 µW/cm² = 1.19 W/m² IRA ( 700 nm - 1400 nm) 65.1 µW/cm² = 0.651 W/m² IR2 ( 720 nm - 1100 nm) 45.9 µW/cm² = 0.459 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 4.29 UV-Index Pyrimidine dimerization of DNA 42.9 µW/cm² Photoceratitis 6.31 µW/cm² Photoconjunctivitis 1.7 µW/cm² DNA Damage 2.13 Vitamin D3 15 µW/cm² Photosynthesis 798 µW/cm² Luminosity 3090 lx Human L-Cone 454 µW/cm² Human M-Cone 401 µW/cm² Human S-Cone 323 µW/cm² CIE X 416 µW/cm² CIE Y 429 µW/cm² CIE Z 594 µW/cm² PAR 5510000 mol photons Extinction preD3 143 e-3*m²/mol Extinction Tachysterol 495 e-3*m²/mol Exctincition PreD3 78800 m²/mol Extinction Lumisterol 26.6 m²/mol Exctincition Tachysterol 750000 m²/mol Extinction 7DHC 27.2 m²/mol L-Cone 372 µW/cm² M-Cone 387 µW/cm² S-Cone 583 µW/cm² U-Cone 290 µW/cm² UVR - ICNIRP 2004 4.04 Rel Biol Eff Melatonin Supression 428 µW/cm² Blue Light Hazard 366 µW/cm² (118 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 16.2 µW/cm² Lumen Reptil 3600 "pseudo-lx" Vitamin D3 Degradation 24.7 µW/cm² Actinic UV 4.03 µW/cm² (13 mW/klm) Exctincition Lumisterol 35300 m²/mol Exctincition 7DHC 31300 m²/mol Exctincition Toxisterols 19900 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 161 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 4.58 Leybold UVB 109 µW/cm² Leybold UVA 438 µW/cm² Leybold UVC 1.33 µW/cm² DeltaOhm UVB 321 µW/cm² DeltaOhm UVC 37.4 µW/cm² Vernier UVB 29.5 µW/cm² Vernier UVA 482 µW/cm² Gröbel UVA 556 µW/cm² Gröbel UVB 50.6 µW/cm² Gröbel UVC 1.39 µW/cm² Luxmeter 3210 lx Solarmeter 6.4 (D3) 14.3 IU/min UVX-31 351 µW/cm² IL UVB 0.0696 µW/cm² IL UVA 477 µW/cm² Solarmeter 6.5 (UVI, post 2010) 3.96 UV-Index Solarmeter 6.2 (UVB, post 2010) 114 µW/cm² (Solarmeter Ratio = 28.7) Solarmeter AlGaN 6.5 UVI sensor 59.4 UV Index GenUV 7.1 UV-Index 3.61 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 15 W/m² Solarmeter 4.0 (UVA) 6.03 mW/cm² LS122 (manuf.) 0.0203 W/m² ISM400 (first guess) 8.54 W/m² LS122 (assumption) 0.392 W/m² ISM400_new 6.88 W/m² Solarmeter 10.0 (Global Power) (assumption) 12.7 W/m²