{"id":421,"date":"2026-01-06T09:33:07","date_gmt":"2026-01-06T09:33:07","guid":{"rendered":"https:\/\/blog.lyco.co.uk\/blog\/?p=421"},"modified":"2026-01-16T16:28:28","modified_gmt":"2026-01-16T16:28:28","slug":"colour-temperature-rendering-explained","status":"publish","type":"post","link":"https:\/\/blog.lyco.co.uk\/blog\/colour-temperature-rendering-explained\/","title":{"rendered":"Colour temperature &amp; rendering explained"},"content":{"rendered":"\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-1 wp-block-group-is-layout-flex\">\n<p class=\"has-small-font-size\">Posted on 20 December 2019<\/p>\n\n\n\n<p class=\"has-small-font-size\">Author: Andrew Evangelidis<\/p>\n\n\n\n<p class=\"has-small-font-size\">Last updated on 9 August 2024<\/p>\n<\/div>\n\n\n\n<p>Colour temperature and colour rendering are terms you\u2019ll see when buying lights, but what exactly do they mean? These specifications will help you choose exactly the lighting you need. They are rooted in physics, but can be simply expressed:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Colour temperature<\/strong>&nbsp;refers to the&nbsp;overall&nbsp;colour of white light. It tells us whether a lamp or light fitting has a warm bias (i.e. red or yellow) or a cool one (i.e. blue).<\/li>\n\n\n\n<li><strong>Colour rendering<\/strong>&nbsp;relates to the&nbsp;underlying&nbsp;colours in any light source. White light is a mixture of many colours, which are not individually visible. To accurately show the colour of any object, that colour must be hiding in the light.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><\/h2>\n\n\n\n<h2 class=\"wp-block-heading\">A useful example \u2013 the sodium street lamp<\/h2>\n\n\n\n<p>Have you ever noticed how, under traditional street lighting, it\u2019s near-impossible to see most colours? This is an exaggerated example of poor colour rendering. It means the colour you\u2019re trying to identify is not contained in the light.<\/p>\n\n\n\n<p>The street light\u2014despite its lowly colour performance\u2014still has an overall colour. Its strong yellow hue gives it an estimated 1800K colour temperature (yellower than any household bulb).<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Kelvin colour temperatures<\/h2>\n\n\n\n<p>Remember that kelvin colour temperatures are counter-intuitive: higher temperatures mean cooler colours (e.g. 2700K is warm and 6500K is cool).<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Technologies<\/h2>\n\n\n\n<p>Lighting technologies have specific colour properties, which may help you make good buying choices:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Incandescent light<\/strong>&nbsp;is always warm in colour temperature (e.g. 2700K) and excellent for colour rendering, containing all colours of the visible spectrum. It is, nonetheless, relatively poor for displaying violet or blue colours, which are muted by its warm bias.<\/li>\n\n\n\n<li><strong>Halogen light<\/strong>&nbsp;is always warm in colour temperature (e.g. 3000K), and excellent for colour rendering. It is better balanced than incandescent light, with stronger radiation of cooler blue and green colours despite its warm hue.<\/li>\n\n\n\n<li><strong>Fluorescent lights<\/strong>&nbsp;are made in all colour temperatures, achieved by varied use of phosphors. Colour rendering is inferior to filament lighting. However, the ability to combine cool colour temperatures with high-quality colour rendering allows some fluorescent lamps to imitate daylight.<\/li>\n\n\n\n<li><strong>LED lights<\/strong>&nbsp;are also made in various colour temperatures. Again, colour rendering is inferior to filament bulbs, though it is of a high enough standard for most purposes. The best colour rendering in LED technology is prohibitively expensive compared to fluorescent equivalents. Dimmable LEDs have the advantage of maintaining their colour at all brightness levels, which is not true of filament lamps.<\/li>\n<\/ul>\n\n\n\n<p>Below are two spectral distribution charts. Very simply, you can deduce from the smooth diagonal of the incandescent bulb that its colour rendering is more predictable than fluorescent lighting (LED is similarly disadvantaged). This benefit is offset by the strong red bias, which subdues violet and blue colours and is controllable in modern technologies.<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-1 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"209\" height=\"153\" src=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/incandescent-spectral-distr.jpg\" alt=\"\" class=\"wp-image-425\"\/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"207\" height=\"153\" src=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/fluorescent-spectral-distri.jpg\" alt=\"\" class=\"wp-image-426\"\/><\/figure>\n<\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\">CRI Ratings<\/h2>\n\n\n\n<p>CRI (colour rendering index) ratings indicate the quality of colour rendering. They measure how accurately a light can render eight colour patches against expected results. The scores represent percentages (e.g. CRI 80 is 80% averaged accuracy). Although this specification is lenient and limited in scope, it gives some indication of quality of light. It says nothing about colour temperature or bias.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Colour choices<\/h2>\n\n\n\n<p>It is widely accepted that the human response to warm lighting is relaxation, whereas cooler lighting makes us more alert and focused. Thus, warm lights are used in homes and hospitality settings, whilst cool lights are found in work places and schools.<\/p>\n\n\n\n<p>In the following examples, we\u2019ll demonstrate alternate lighting choices in related applications:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Restaurant lighting<\/h3>\n\n\n\n<p>In the dining area of a restaurant, a light such as the\u00a0<a href=\"https:\/\/www.lyco.co.uk\/1488-springsteen-metal-and-glass-pendant-lamp.html?id_c=2620\">Edit Springsteen Ceiling Pendant<\/a>\u00a0is bound to create an impression. Here, you\u2019d want to fit a warm white lamp to emphasise the shade and create a relaxing mood.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"300\" src=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/downlights-300x300-1.jpg\" alt=\"\" class=\"wp-image-424\" srcset=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/downlights-300x300-1.jpg 300w, https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/downlights-300x300-1-150x150.jpg 150w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/figure>\n\n\n\n<p>Back in the kitchen,\u00a0<a href=\"https:\/\/www.lyco.co.uk\/15315-led-panels?filters=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\" target=\"_blank\" rel=\"noreferrer noopener\">cool white LED light panels<\/a>\u00a0will help staff to stay focused and alert. Cooler light also appears brighter to humans, and in the case of LEDs is slightly more energy efficient.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Retail lighting<\/h3>\n\n\n\n<p>In a furniture shop, you\u2019d need warm light to emulate residential lighting. High-quality colour rendering is important to ensure vivid, accurate colours. Try using\u00a0<a href=\"https:\/\/www.lyco.co.uk\/15480-spotlights\" data-type=\"link\" data-id=\"httpstlights.html\">LED Spot and Track lights<\/a>\u00a0to focus lighting at your displays, alongside warm\u00a0<a href=\"https:\/\/www.lyco.co.uk\/15260-floor-lamps\">floor lamps<\/a>\u00a0to replicate the customers home.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"300\" src=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/43819_14_2-300x300-1.jpg\" alt=\"\" class=\"wp-image-423\" srcset=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/43819_14_2-300x300-1.jpg 300w, https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/43819_14_2-300x300-1-150x150.jpg 150w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/figure>\n\n\n\n<p>A cool white light might be used in a shop such as a fish mongers. The aim is to emphasise the colour of the product. The&nbsp;<a href=\"https:\/\/www.lyco.co.uk\/flash-40w-cool-white-led-recessed-rectangular-display-light.html\">Flash recessed display light<\/a>&nbsp;is a good option in this instance.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Picture lights<\/h3>\n\n\n\n<p><a href=\"https:\/\/www.lyco.co.uk\/15440-picture-lights\">Picture lights<\/a>\u00a0have improved greatly since the original halogen options. LED fittings are now both better value, but also better for the photo or artwork it is adorning. They give off minimal UV radiation compared to their halogen and incandescent predecessors, therefore they emit no harmful toxins and are safe to use for many years.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"300\" src=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/45599_14-1-300x300-1.jpg\" alt=\"\" class=\"wp-image-422\" srcset=\"https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/45599_14-1-300x300-1.jpg 300w, https:\/\/blog.lyco.co.uk\/blog\/wp-content\/uploads\/2026\/01\/45599_14-1-300x300-1-150x150.jpg 150w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/figure>\n\n\n\n<p>For more lighting information, advice and ideas take a look at our\u00a0<a href=\"https:\/\/blog.lyco.co.uk\/blog\/\">Lighting Blog section<\/a>.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Posted on 20 December 2019 Author: Andrew Evangelidis Last updated on 9 August 2024 Colour temperature and colour rendering are terms you\u2019ll see when buying lights, but what exactly do they mean? These specifications will help you choose exactly the lighting you need. They are rooted in physics, but can be simply expressed: A useful [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":427,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-421","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sin-categoria"],"_links":{"self":[{"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/posts\/421","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/comments?post=421"}],"version-history":[{"count":3,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/posts\/421\/revisions"}],"predecessor-version":[{"id":552,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/posts\/421\/revisions\/552"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/media\/427"}],"wp:attachment":[{"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/media?parent=421"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/categories?post=421"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.lyco.co.uk\/blog\/wp-json\/wp\/v2\/tags?post=421"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}