![\"V(\u03bb)](\"https:\/\/designinglight.com\/wp-content\/uploads\/2017\/01\/VL-and-Red.png\")
<\/a><\/p>\nLight meters measure the light that the colored LEDs provide, of course, and this information is included on an LED fixture manufacturer\u2019s cut sheets, but it often makes no sense. For example, an RGBW fixture I’ve arbitrarily selected\u00a0reports the following output in lumens: Red 388, Green 1,039, Blue 85, White 1,498. Since brightness is additive, the output when all LEDs are at full should be 3,010 lumens. However the Full RGBW output is given as 2,805 lumens! That\u2019s 7% lower than what we expect.<\/p>\n
The essential problem is that the colored LEDs give the light meter only a fraction of the spectrum it\u2019s designed to measure. The meter provides\u00a0a result based on its programming and calibration, but the results are often nonsensical or at odds with our perception. This problem doesn\u2019t affect only architectural lighting designers. Film and TV directors of photography and lighting directors also rely on a light meter\u2019s accurate measurement of brightness in their work, and when using colored LED fixtures the light meter is likely to be wrong. In fact, even white light LEDs can be difficult to measure accurately because of the blue spike in their SPD.<\/p>\n
For now, the only way to accurately assess the brightness of colored LEDs is to see them in use. Lighting professionals need to let manufacturers and others know that the current situation is not acceptable, and that an accurate method of measuring and reporting the brightness of colored LEDs is a high priority. Talk to fixture and lamp sales reps, fixture and lamp manufacturers, and decision makers at IES, CIE, NIST and other research and standards setting organizations. There\u2019s a solution out there. We need to urge those with the skills and resources to find it to get going!<\/p>\n","protected":false},"excerpt":{"rendered":"
Measuring and describing the brightness of colored LEDs is an increasingly important part of a lighting designer\u2019s practice. They are used more often, and in more types of projects, than ever before. Yet, we don\u2019t have an accurate method for understanding exactly how much light is being produced and how bright it will appear. It\u2019s … Continue reading How Bright Are Colored LEDs?<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[12,18,11,17],"tags":[61,34,24],"class_list":["post-676","post","type-post","status-publish","format-standard","hentry","category-color","category-design","category-leds","category-light","tag-color-perception","tag-design-2","tag-led-color"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p4gZSw-aU","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"jetpack-related-posts":[{"id":681,"url":"https:\/\/designinglight.com\/?p=681","url_meta":{"origin":676,"position":0},"title":"Lighting For Plant Health","author":"Jason Livingston","date":"February 28, 2017","format":false,"excerpt":"I have a current project with a green wall, aka living wall, and other greenery in the space. I\u2019ve been given conflicting information about the lighting requirements I need to meet are and how to measure them, so I did some research. This isn\u2019t definitive, but here\u2019s what I\u2019ve found.\u2026","rel":"","context":"In "Design"","block_context":{"text":"Design","link":"https:\/\/designinglight.com\/?cat=18"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/designinglight.com\/wp-content\/uploads\/2017\/01\/VLambda-300x227.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":692,"url":"https:\/\/designinglight.com\/?p=692","url_meta":{"origin":676,"position":1},"title":"LRC Responds to AMA on LEDs","author":"Jason Livingston","date":"March 27, 2017","format":false,"excerpt":"You may remember that in June of last year the American Medical Association (AMA) released a report called \u201cHuman and Environmental Effects of Light Emitting Diode (LED) Community Lighting.\u201d The report made some noise in the general press because it supported the idea that blue light from blue-pump white LEDs\u2026","rel":"","context":"In "Color"","block_context":{"text":"Color","link":"https:\/\/designinglight.com\/?cat=12"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":203,"url":"https:\/\/designinglight.com\/?p=203","url_meta":{"origin":676,"position":2},"title":"Light and Health","author":"Jason Livingston","date":"July 28, 2014","format":false,"excerpt":"The DOE has recently published a fact sheet titled Lighting for Health: LEDs in the New Age of Illumination.\u00a0\u00a0 It summarizes the Trends in Neuroscience January 2014 article Measuring and Using Light in the Melanopsin Age.\u00a0 Both publications explain the current understanding of our visual and nonvisual response to light.\u2026","rel":"","context":"In "Health"","block_context":{"text":"Health","link":"https:\/\/designinglight.com\/?cat=3"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":592,"url":"https:\/\/designinglight.com\/?p=592","url_meta":{"origin":676,"position":3},"title":"Who Needs A Lighting Designer? Museums and Galleries!","author":"Jason Livingston","date":"January 28, 2016","format":false,"excerpt":"A few weeks ago I gave a three-hour seminar on lighting museums and galleries to the graduate students in an art curating program at a university here in New York. Condensing everything I\u2019d like to say into less than three hours was tough. The two big questions were what to\u2026","rel":"","context":"In "Color"","block_context":{"text":"Color","link":"https:\/\/designinglight.com\/?cat=12"},"img":{"alt_text":"Illuminated with Warm White Fluorescent Lamp","src":"https:\/\/i0.wp.com\/designinglight.com\/wp-content\/uploads\/2014\/11\/Color-Shift-3000K-Fl-300x189.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":622,"url":"https:\/\/designinglight.com\/?p=622","url_meta":{"origin":676,"position":4},"title":"MIT Creates Incandescent Lamp As Efficient as LEDs","author":"Jason Livingston","date":"April 25, 2016","format":false,"excerpt":"Researchers at MIT and Purdue University have demonstrated an incandescent lamp with an efficacy of 6.6 percent, and with a potential efficacy as high as 40 percent. The paper was published in the April issue of Nature Nanotechnology. The demonstration compares favorably to current low efficacy fluorescent and LED lamps,\u2026","rel":"","context":"In "Lamps"","block_context":{"text":"Lamps","link":"https:\/\/designinglight.com\/?cat=13"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1015,"url":"https:\/\/designinglight.com\/?p=1015","url_meta":{"origin":676,"position":5},"title":"Do LEDs Make You Look Orange?","author":"Jason Livingston","date":"September 16, 2019","format":false,"excerpt":"Last Thursday Donald Trump spoke to a group of Republicans in Baltimore.\u00a0\u00a0One of the things he said caught my attention: \u201cThe lightbulb. People said what\u2019s with the lightbulb? I said, here\u2019s the story. And I looked at it, the bulb that we\u2019re being forced to use, No. 1, to me,\u2026","rel":"","context":"In "Color"","block_context":{"text":"Color","link":"https:\/\/designinglight.com\/?cat=12"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/designinglight.com\/wp-content\/uploads\/2017\/10\/CES-SPD.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/designinglight.com\/wp-content\/uploads\/2017\/10\/CES-SPD.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/designinglight.com\/wp-content\/uploads\/2017\/10\/CES-SPD.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/designinglight.com\/wp-content\/uploads\/2017\/10\/CES-SPD.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/designinglight.com\/index.php?rest_route=\/wp\/v2\/posts\/676","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/designinglight.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/designinglight.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/designinglight.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/designinglight.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=676"}],"version-history":[{"count":2,"href":"https:\/\/designinglight.com\/index.php?rest_route=\/wp\/v2\/posts\/676\/revisions"}],"predecessor-version":[{"id":678,"href":"https:\/\/designinglight.com\/index.php?rest_route=\/wp\/v2\/posts\/676\/revisions\/678"}],"wp:attachment":[{"href":"https:\/\/designinglight.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=676"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/designinglight.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=676"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/designinglight.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=676"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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