Ten real spectral instruments shown with verified Wikimedia Commons photographs: Bunsen-Kirchhoff spectroscopes, prism laboratory systems, Bragg's X-ray spectrometer, an ESI mass spectrometer, an NMR spectrometer, and astronomical spectrographs. Photograph credits: 1. File:Spettroscopio Bunsen Kirchhoff.jpg; MuMiCaserta; CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0; https://commons.wikimedia.org/wiki/File:Spettroscopio_Bunsen_Kirchhoff.jpg; 2. File:Direct vision spectroscope, J. G. Hofmann, Paris, before 1871 - Museu da Ciência da Universidade de Coimbra - University of Coimbra - Coimbra, Portugal - DSC09081.jpg; Daderot; CC0 1.0; https://creativecommons.org/publicdomain/zero/1.0/; https://commons.wikimedia.org/wiki/File:Direct_vision_spectroscope,_J._G._Hofmann,_Paris,_before_1871_-_Museu_da_Ci%C3%AAncia_da_Universidade_de_Coimbra_-_University_of_Coimbra_-_Coimbra,_Portugal_-_DSC09081.jpg; 3. File:Six-prism solar spectroscope, World Museum Liverpool.jpg; Reptonix free Creative Commons licensed photos; CC BY 3.0; https://creativecommons.org/licenses/by/3.0; https://commons.wikimedia.org/wiki/File:Six-prism_solar_spectroscope,_World_Museum_Liverpool.jpg; 4. File:Spectroscope from Physics Department.jpg; University of Dundee Museum Services; CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0; https://commons.wikimedia.org/wiki/File:Spectroscope_from_Physics_Department.jpg; 5. File:Bausch & Lomb Spectroscope - DPLA - 83997f3a582cc850619eda064d206a8b (page 2).jpg; Bausch & Lomb Optical Company; Public domain; ; https://commons.wikimedia.org/wiki/File:Bausch_%26_Lomb_Spectroscope_-_DPLA_-_83997f3a582cc850619eda064d206a8b_(page_2).jpg; 6. File:X-ray spectrometer, 1912. (9660569929).jpg; Science Museum London / Science and Society Picture Library; CC BY-SA 2.0; https://creativecommons.org/licenses/by-sa/2.0; https://commons.wikimedia.org/wiki/File:X-ray_spectrometer,_1912._(9660569929).jpg; 7. File:Fenn ESI Instrument.jpg; Jeff Dahl; CC BY-SA 3.0; https://creativecommons.org/licenses/by-sa/3.0; https://commons.wikimedia.org/wiki/File:Fenn_ESI_Instrument.jpg; 8. File:Bruker NMR Spectrometer.jpg; LMmcstd; CC BY-SA 4.0; https://creativecommons.org/licenses/by-sa/4.0; https://commons.wikimedia.org/wiki/File:Bruker_NMR_Spectrometer.jpg; 9. File:Echelle Spectrograph (noao-02614).jpg; NOIRLab/ NSF /AURA; CC BY 4.0; https://creativecommons.org/licenses/by/4.0; https://commons.wikimedia.org/wiki/File:Echelle_Spectrograph_(noao-02614).jpg; 10. File:The KMOS spectrograph before shipping to Chile.jpg; STFC/UKATC/ESO; CC BY 3.0; https://creativecommons.org/licenses/by/3.0; https://commons.wikimedia.org/wiki/File:The_KMOS_spectrograph_before_shipping_to_Chile.jpg;