Spectrometer Error Testing
Test 2: New dark spectrum stored and absolute irradiance recalculated for every set of data
22:47
Spectrum 382: BA32 Edit
DeleteMeasurement
| Brand |
Arcadia UK company https://www.arcadiareptile.com/ |
|---|---|
| Lamp Product |
Arcadia D3+ Dragon 14% Reptile Lamp T5 24W |
| Lamp ID |
BA32 (02/2011) |
| Spectrometer | USB2000+ (2) |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | |
| Distance | 10 cm |
| Age | 2,750 hours |
| Originator (measurement) | Frances Baines |
Database entry created:
Sarina Wunderlich
5/Feb/2011 ; 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 | ( 0.3 ; 0.29 ) | ( 0.35 ; 0.47 ) | ( 0.25 ; 0.26 ; 0.36 ) |
| CCT | 7900 Kelvin | 6000 Kelvin | 6000 Kelvin |
| distance | 0.13 | 0.098 | |
| 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) 1240 µW/cm² = 12.4 W/m² UVC ( 0 nm - 280 nm) 2.85 µW/cm² = 0.0285 W/m² non-terrestrial ( 0 nm - 290 nm) 3.79 µW/cm² = 0.0379 W/m² total2 ( 250 nm - 880 nm) 1240 µW/cm² = 12.4 W/m² UVB (EU) ( 280 nm - 315 nm) 59.1 µW/cm² = 0.591 W/m² UVB (US) ( 280 nm - 320 nm) 93.4 µW/cm² = 0.934 W/m² UVA+B ( 280 nm - 380 nm) 394 µW/cm² = 3.94 W/m² Solar UVB ( 290 nm - 315 nm) 58.2 µW/cm² = 0.582 W/m² UVA D3 regulating ( 315 nm - 335 nm) 149 µW/cm² = 1.49 W/m² UVA (EU) ( 315 nm - 380 nm) 335 µW/cm² = 3.35 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 156 µW/cm² = 1.56 W/m² UVA (US) ( 320 nm - 380 nm) 301 µW/cm² = 3.01 W/m² UVA1 (variant) ( 335 nm - 380 nm) 186 µW/cm² = 1.86 W/m² UVA1 (medical) ( 340 nm - 400 nm) 152 µW/cm² = 1.52 W/m² vis. UVA ( 350 nm - 380 nm) 79.3 µW/cm² = 0.793 W/m² VIS Rep3 ( 350 nm - 600 nm) 676 µW/cm² = 6.76 W/m² VIS Rep4 ( 350 nm - 700 nm) 833 µW/cm² = 8.33 W/m² purple ( 380 nm - 420 nm) 47.6 µW/cm² = 0.476 W/m² VIS ( 380 nm - 780 nm) 794 µW/cm² = 7.94 W/m² VIS2 ( 400 nm - 680 nm) 738 µW/cm² = 7.38 W/m² PAR ( 400 nm - 700 nm) 746 µW/cm² = 7.46 W/m² tmp ( 400 nm - 1100 nm) 837 µW/cm² = 8.37 W/m² blue ( 420 nm - 490 nm) 268 µW/cm² = 2.68 W/m² green ( 490 nm - 575 nm) 223 µW/cm² = 2.23 W/m² yellow ( 575 nm - 585 nm) 27.6 µW/cm² = 0.276 W/m² orange ( 585 nm - 650 nm) 161 µW/cm² = 1.61 W/m² red ( 650 nm - 780 nm) 66.7 µW/cm² = 0.667 W/m² IRA ( 700 nm - 1400 nm) 90.6 µW/cm² = 0.906 W/m² IR2 ( 720 nm - 1100 nm) 78.8 µW/cm² = 0.788 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
Actionspectra
Erythema 4.71 UV-Index Pyrimidine dimerization of DNA 34.6 µW/cm² Photoceratitis 6.63 µW/cm² Photoconjunctivitis 2.69 µW/cm² DNA Damage 3.35 Vitamin D3 14.9 µW/cm² Photosynthesis 530 µW/cm² Luminosity 2120 lx Human L-Cone 315 µW/cm² Human M-Cone 268 µW/cm² Human S-Cone 219 µW/cm² CIE X 301 µW/cm² CIE Y 293 µW/cm² CIE Z 407 µW/cm² PAR 3470000 mol photons Extinction preD3 127 e-3*m²/mol Extinction Tachysterol 412 e-3*m²/mol Exctincition PreD3 73900 m²/mol Extinction Lumisterol 38 m²/mol Exctincition Tachysterol 580000 m²/mol Extinction 7DHC 41.3 m²/mol L-Cone 260 µW/cm² M-Cone 278 µW/cm² S-Cone 379 µW/cm² U-Cone 144 µW/cm² UVR - ICNIRP 2004 5.31 Rel Biol Eff Melatonin Supression 292 µW/cm² Blue Light Hazard 245 µW/cm² (115 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 16.2 µW/cm² Lumen Reptil 2390 "pseudo-lx" Vitamin D3 Degradation 19.1 µW/cm² Actinic UV 5.28 µW/cm² (24.8 mW/klm) Exctincition Lumisterol 46100 m²/mol Exctincition 7DHC 46000 m²/mol Exctincition Toxisterols 20300 m²/mol
Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 116 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 4.55 Leybold UVB 80 µW/cm² Leybold UVA 212 µW/cm² Leybold UVC 2.14 µW/cm² DeltaOhm UVB 193 µW/cm² DeltaOhm UVC 25.6 µW/cm² Vernier UVB 27.2 µW/cm² Vernier UVA 251 µW/cm² Gröbel UVA 282 µW/cm² Gröbel UVB 40.5 µW/cm² Gröbel UVC 2.27 µW/cm² Luxmeter 2160 lx Solarmeter 6.4 (D3) 14.2 IU/min UVX-31 208 µW/cm² IL UVB 0.0481 µW/cm² IL UVA 237 µW/cm² Solarmeter 6.5 (UVI, post 2010) 3.77 UV-Index Solarmeter 6.2 (UVB, post 2010) 76.6 µW/cm² (Solarmeter Ratio = 20.3) Solarmeter AlGaN 6.5 UVI sensor 49.2 UV Index GenUV 7.1 UV-Index 2.87 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 10.4 W/m² Solarmeter 4.0 (UVA) 3.03 mW/cm² LS122 (manuf.) 0.0373 W/m² ISM400 (first guess) 6.66 W/m² LS122 (assumption) 0.315 W/m² ISM400_new 5.67 W/m² Solarmeter 10.0 (Global Power) (assumption) 9.11 W/m²