Constructor of red wavebandSource:
Wavelength-range definitions for red light according to ISO or as commonly used in plant or remote sensing applications.
a character string, one of "ISO", "Smith10", "Smith20", "Inada", "Warrington", "Sellaro", "RS", "LandsatOLI", "LandsatTM", "LandsatETM", "LandsatMSS", and "LandsatRBV".
The different arguments passed to formal parameter
determine the range of wavelengths set as boundaries of the returned
"ISO" is an standardized
definition based on human colour vision;
"Broad" are non-standard but used in plant sciences;
non-standard but frequently used in remote sensing; the remaining
definitions are for the published wavelength sensitivity range of imagers
(cameras) in the Landsat satellite missions.
In plant photobiology the definitions proposed by Prof. Harry Smith are the most widely used, specially to compute a red to far-red photon ratio relevant to phytochrome photoreceptors. However, other authors have used different definitions in their publications. "Smith10" (655-665 nm), "Smith20" (650-670 nm), "Inada" (600-700 nm), "Warrington" (625-675 nm), and "Sellaro" (620-680 nm).
The bands are defined as square windows, these can be applied to spectral data to obtain the "true" values, but they do not simulate the sensitivity of broad-band sensors or the spectral transmittance of ionic filters. Some band-pass interference filters may have very sharp cut-in and cut-off, and their effect can be approximated by a square window, but filters based on light absorption will show gradual tails and bell-shaped wavelength-windows. The Landsat instruments have very steep cut-in and cut-off slopes and are well approximated.
Aphalo, P. J., Albert, A., Björn, L. O., McLeod, A. R., Robson, T. M., Rosenqvist, E. (Eds.). (2012). Beyond the Visible: A handbook of best practice in plant UV photobiology (1st ed., p. xxx + 174). Helsinki: University of Helsinki, Department of Biosciences, Division of Plant Biology. ISBN 978-952-10-8363-1 (PDF), 978-952-10-8362-4 (paperback). Open access PDF download available at doi:10.31885/9789521083631 .
ISO (2007) Space environment (natural and artificial) - Process for determining solar irradiances. ISO Standard 21348. ISO, Geneva.
Murakami, K., Aiga I. (1994) Red/Far-red photon flux ratio used as an index number for morphological control of plant growth under artificial lighting conditions. Proc. Int. Symp. Artificial Lighting, Acta Horticulturae, 418, ISHS 1997.
Sellaro, R., Crepy, M., Trupkin, S. A., Karayekov, E., Buchovsky, A. S., Rossi, C., & Casal, J. J. (2010). Cryptochrome as a sensor of the blue/green ratio of natural radiation in Arabidopsis. Plant physiology, 154(1), 401-409. doi:10.1104/pp.110.160820 .
Smith, H. (1982) Light quality, photoperception and plant strategy. Annual Review of Plant Physiology, 33:481-518. doi:10.1146/annurev.pp.33.060182.002405
Red() #> Red.ISO #> low (nm) 610 #> high (nm) 760 #> weighted none Red("ISO") #> Red.ISO #> low (nm) 610 #> high (nm) 760 #> weighted none Red("Smith") #> Warning: The definition of 'Smith' defaults to 'Smith10'. #> Red.Smith10 #> low (nm) 655 #> high (nm) 665 #> weighted none Red("Sellaro") #> Red.Sellaro #> low (nm) 620 #> high (nm) 680 #> weighted none e_irrad(sun.spct, Red()) # W m-2 #> E_Red.ISO #> 79.38159 #> attr(,"time.unit") #>  "second" #> attr(,"radiation.unit") #>  "total energy irradiance" q_irrad(sun.spct, Red()) # mol m-2 #> Q_Red.ISO #> 0.0004511083 #> attr(,"time.unit") #>  "second" #> attr(,"radiation.unit") #>  "total photon irradiance" q_irrad(sun.spct, Red(), scale.factor = 1e6) # umol m-2 #> Q_Red.ISO #> 451.1083 #> attr(,"time.unit") #>  "second" #> attr(,"radiation.unit") #>  "total photon irradiance"