Spectrum #862 Robinson2026Fig1a2 (Light Power Health UK standard+850) Edit
Delete(1) Raw Measurement
| Lampid | Robinson2026Fig1a2 |
|---|---|
| Spectrometer | - |
| Originator | Publication |
| Ballast | - no ballast or default/unknown ballast - |
| Reflector | - no reflector - |
| Distance | 0 |
| Age | 0 |
created by Sarina Wunderlich, 01.10.2026; last updated by , 01.10.2026
Description
(2) Comparison of full spectrum to sunlight
The spectrum is compared to the ASTM spectrum. The measured spectrum is scaled to a lux or UVI value that seems to "make sense" to the database. This can go wrong, depending on the quality and range of the data.
(3) 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 (ASTM spectrum).
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 | ( 0.46 ; 0.41 ) | ( 0.65 ; 0.32 ) | ( 0.57 ; 0.28 ; 0.13 ) |
| CCT | 2700 Kelvin | 2600 Kelvin | 2600 Kelvin |
| distance | 0.049 | 0.02 | |
| colour space | 3-D-graph not implemented yet |
(4) 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 readings of two solarmeters 6.2 (UVB) and 6.5 (UV index) has proven a useful and very simply number to acess the spectral shape in the vitamin-d3-active region.
(5) 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
(5a) Ranges
total ( 0 nm - 0 nm) 9.02 µW/cm² = 0.0902 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) 8.86 µW/cm² = 0.0886 W/m² UVB (EU) ( 280 nm - 315 nm) 0.000611 µW/cm² = 6.11E-6 W/m² UVB (US) ( 280 nm - 320 nm) 0.000839 µW/cm² = 8.39E-6 W/m² UVA+B ( 280 nm - 380 nm) 0.003 µW/cm² = 3.0E-5 W/m² Solar UVB ( 290 nm - 315 nm) 0.000611 µW/cm² = 6.11E-6 W/m² UVA D3 regulating ( 315 nm - 335 nm) 0.000803 µW/cm² = 8.03E-6 W/m² UVA (EU) ( 315 nm - 380 nm) 0.00239 µW/cm² = 2.39E-5 W/m² UVA2 (medical definition) ( 320 nm - 340 nm) 0.000818 µW/cm² = 8.18E-6 W/m² UVA (US) ( 320 nm - 380 nm) 0.00217 µW/cm² = 2.17E-5 W/m² UVA1 (variant) ( 335 nm - 380 nm) 0.00158 µW/cm² = 1.58E-5 W/m² UVA1 (medical) ( 340 nm - 400 nm) 0.00234 µW/cm² = 2.34E-5 W/m² vis. UVA ( 350 nm - 380 nm) 0.000992 µW/cm² = 9.92E-6 W/m² VIS Rep3 ( 350 nm - 600 nm) 1.25 µW/cm² = 0.0125 W/m² VIS Rep4 ( 350 nm - 700 nm) 2.74 µW/cm² = 0.0274 W/m² purple ( 380 nm - 420 nm) 0.0232 µW/cm² = 0.000232 W/m² VIS ( 380 nm - 780 nm) 3.03 µW/cm² = 0.0303 W/m² VIS2 ( 400 nm - 680 nm) 2.55 µW/cm² = 0.0255 W/m² PAR ( 400 nm - 700 nm) 2.74 µW/cm² = 0.0274 W/m² blue ( 420 nm - 490 nm) 0.231 µW/cm² = 0.00231 W/m² green ( 490 nm - 575 nm) 0.689 µW/cm² = 0.00689 W/m² yellow ( 575 nm - 585 nm) 0.113 µW/cm² = 0.00113 W/m² orange ( 585 nm - 650 nm) 1.05 µW/cm² = 0.0105 W/m² tmp ( 600 nm - 1000 nm) 7.77 µW/cm² = 0.0777 W/m² red ( 650 nm - 780 nm) 0.922 µW/cm² = 0.00922 W/m² IR2 ( 655 nm - 685 nm) 0.414 µW/cm² = 0.00414 W/m² IRA ( 700 nm - 1400 nm) 6.28 µW/cm² = 0.0628 W/m² IRB ( 1400 nm - 3000 nm) 0 µW/cm² = 0 W/m²
(5b) Actionspectra
Erythema 5.12E-5 UV-Index Pyrimidine dimerization of DNA 0.000456 µW/cm² Photoceratitis 7.7E-5 µW/cm² Photoconjunctivitis 1.35E-6 µW/cm² DNA Damage 4.48E-6 Vitamin D3 0.00025 µW/cm² Photosynthesis 1.86 µW/cm² Luminosity 8 lx Human L-Cone 1.27 µW/cm² Human M-Cone 0.851 µW/cm² Human S-Cone 0.188 µW/cm² CIE X 1.26 µW/cm² CIE Y 1.11 µW/cm² CIE Z 0.362 µW/cm² PAR PPFD 0.136 µmol/m²/s Extinction preD3 0.00112 e-3*m²/mol Extinction Tachysterol 0.00376 e-3*m²/mol Exctincition PreD3 0.508 m²/mol Extinction Lumisterol 0.000226 m²/mol Exctincition Tachysterol 5.04 m²/mol Extinction 7DHC 0.000146 m²/mol L-Cone 1.19 µW/cm² M-Cone 0.579 µW/cm² S-Cone 0.28 µW/cm² U-Cone 0.0263 µW/cm² UVR - ICNIRP 2004 4.39E-5 Rel Biol Eff Melatonin Supression 0.323 µW/cm² Blue Light Hazard 0.212 µW/cm² (26.5 µW/cm² per 1000 lx) CIE 174:2006 PreVit D3 0.000286 µW/cm² Lumen Reptil 5.69 "pseudo-lx" Vitamin D3 Degradation 0.000179 µW/cm² Actinic UV 4.25E-5 µW/cm² (0.0531 mW/klm) Exctincition Lumisterol 0.306 m²/mol Exctincition 7DHC 0.195 m²/mol Exctincition Toxisterols 0.0703 m²/mol UV-Index2 5.12E-5 UV-Index (285-400nm)
(5c) Broadbandmeters
Solarmeter 6.2 (UVB, pre 2010) 0.000972 µW/cm² Solarmeter 6.5 (UV-Index, pre 2010) 7.0E-5 Leybold UVB 0.000751 µW/cm² Leybold UVA 0.00161 µW/cm² Leybold UVC 0 µW/cm² DeltaOhm UVB 0.00128 µW/cm² DeltaOhm UVC 0.000179 µW/cm² Vernier UVB 0.000387 µW/cm² Vernier UVA 0.00158 µW/cm² Gröbel UVA 0.00199 µW/cm² Gröbel UVB 0.00046 µW/cm² Gröbel UVC 2.4E-7 µW/cm² Luxmeter 7.56 lx Solarmeter 6.4 (D3) 0.000219 IU/min UVX-31 0.00144 µW/cm² IL UVB 4.23E-7 µW/cm² IL UVA 0.00185 µW/cm² Solarmeter 6.5 (UVI, post 2010) 5.59E-5 UV-Index Solarmeter 6.2 (UVB, post 2010) 0.000582 µW/cm² (Solarmeter Ratio = 10.4) Solarmeter AlGaN 6.5 UVI sensor 0.000568 UV Index GenUV 7.1 UV-Index 2.9E-5 UV-Index Solarmeter 10.0 (Global Power) (manuf.) 0.142 W/m² Solarmeter 4.0 (UVA) 3.45E-5 mW/cm² LS122 (manuf.) 0.0167 W/m² ISM400 (first guess) 0.17 W/m² LS122 (assumption) 0.0155 W/m² ISM400_new 0.189 W/m² Solarmeter 10.0 (Global Power) (assumption) 0.146 W/m²
(5d) Summary of my favourites
| UVC (0nm -280nm) [µW/cm] | 0 | 0 % |
| non-terrestrial (0nm -290nm) [µW/cm] | 0 | 0 % |
| UVB (EU) (280nm -315nm) [µW/cm] | 0.000611 | 0.0069 % |
| UVB (US) (280nm -320nm) [µW/cm] | 0.000839 | 0.00947 % |
| Solar UVB (290nm -315nm) [µW/cm] | 0.000611 | 0.0069 % |
| UVA (EU) (315nm -380nm) [µW/cm] | 0.00239 | 0.027 % |
| UVA (US) (320nm -380nm) [µW/cm] | 0.00217 | 0.0244 % |
| UVA2 (medical definition) (320nm -340nm) [µW/cm] | 0.000818 | 0.00923 % |
| UVA1 (medical) (340nm -400nm) [µW/cm] | 0.00234 | 0.0264 % |
| UVA D3 regulating (315nm -335nm) [µW/cm] | 0.000803 | 0.00906 % |
| vis. UVA (350nm -380nm) [µW/cm] | 0.000992 | 0.0112 % |
| VIS (380nm -780nm) [µW/cm] | 3.03 | 34.1 % |
| blue (420nm -490nm) [µW/cm] | 0.231 | 2.6 % |
| total2 (250nm -880nm) [µW/cm] | 8.86 | 100 % |
| UV-Index2 [UV-Index] | 5.12E-5 | |
| Luminosity [lx] | 8 | |
| Blue Light Hazard [µW/cm²] | 0.212 | 26.5µW/cm/1000lx |
| Solarmeter 6.5 (UVI, post 2010) [UV-Index] | 5.59E-5 | |
| Solarmeter 6.2 (UVB, post 2010) [µW/cm²] | 0.000582 | |
| Actinic UV [µW/cm²] | 4.25E-5 | 6.31 at UVI7.6 |
| Vitamin D3 [µW/cm²] | 0.00025 | 37.1 at UVI7.6 |