{"id":261,"date":"2006-10-03T17:45:30","date_gmt":"2006-10-03T08:45:30","guid":{"rendered":"https:\/\/regex.info\/blog\/photo-tech\/color-spaces-page7"},"modified":"2006-10-03T13:38:18","modified_gmt":"2006-10-03T04:38:18","slug":"color-spaces-page7","status":"publish","type":"page","link":"https:\/\/regex.info\/blog\/photo-tech\/color-spaces-page7","title":{"rendered":"Digital-Image Color Spaces, Page 7: Recommendations and Links"},"content":{"rendered":"\n\n<style type='text\/css'>\na.btn    { background-color: #555; border: solid 1px #888; padding: 2px 5px }\nspan.now { background-color: #533; border: solid 1px #888; padding: 2px 5px; font-weight: bold }\n<\/style>\n<div style='display: block; background-color: #444; padding: 7px; border: solid 2px gray'>\n<b>Article:<\/b>\n<a class='btn' href='\/blog\/photo-tech\/color-spaces-page0\/'>Table of Contents<\/a> &nbsp; &nbsp; &nbsp; <b>Page:<\/b>\n<a title='Introduction' class='btn' href='\/blog\/photo-tech\/color-spaces-page1\/'>1<\/a> &middot;\n<a title='Test Images' class='btn' href='\/blog\/photo-tech\/color-spaces-page2\/'>2<\/a> &middot;\n<a title='Color Mis-Management' class='btn' href='\/blog\/photo-tech\/color-spaces-page3\/'>3<\/a> &middot;\n<a title='Color Management' class='btn' href='\/blog\/photo-tech\/color-spaces-page4\/'>4<\/a> &middot;\n<a title='Chromaticity Diagrams' class='btn' href='\/blog\/photo-tech\/color-spaces-page5\/'>5<\/a> &middot;\n<a title='Design Tradeoffs' class='btn' href='\/blog\/photo-tech\/color-spaces-page6\/'>6<\/a> &middot;\n<span class='now'>7<\/span><small>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This is the final page of <span class='nobr'>a seven<\/span>-page article<\/small>\n\n<\/div>\n\n<p><a name='Perfect'><b>Perfect Colors?<\/b><\/a><\/p>\n\n<p>Okay, so let's say that you have an image file with an embedded color\nprofile, <span class='nobr'>a properly<\/span>-profiled monitor, and an application that respects both\nprofiles: will you finally see the proper, true colors?\n\n<\/p><p>\n\nMaybe.\n\n<\/p><p>\n\nFirst, you must define &#8220;true color.&#8221; If you define it as the\ncolors <i>as encoded in the image<\/i>, then you'll see them properly to the\nextent that your monitor can actually display the image's full range of\ncolors. <span class='nobr'>A monitor<\/span> or printer can only produce the colors, that, er, it has\nthe physical ability to produce. If it's <span class='nobr'>a particularly<\/span> wide color space,\nand not <span class='nobr'>a particularly<\/span> high-caliber monitor, colors will be clipped in the\nprocess of display.\n\n<\/p><p>\n\nIf you define &#8220;true color&#8221; as those colors as they existed when\nthe camera first attempted to capture them, you have many, many more\nvariables. These include the characteristics of the camera's sensor, the\nwhite-balance settings (and other settings such as exposure and\nsaturation), the color space used to encode the image (are true colors\nclipped to fit inside the color space? <span class='nobr'>Do true colors<\/span> need to be\n&#8220;fudged&#8221; so that they match <span class='nobr'>a color<\/span> actually encodable within\nthe space?), and any lossy compression used to encode the image.\n\n<\/p><p>Of course, even if you could see the true colors, you still might\nnot like the image &mdash; in the end, there's no accounting for artistic\ntaste <b>\ud83d\ude42<\/b><\/p>\n\n<p><b><a name='Suggestions1'>Suggestions for the Digital Photographer<\/a><\/b><\/p>\n\n<p>The two most important recommendations:<\/p>\n\n<ol>\n  <li><p><b>Embed color profiles in all images<\/b>. This lets color-managed systems know exactly how to treat the color data in your image.<\/p><\/li>\n\n  <li><p><b>When preparing <span class='nobr'>a photo<\/span> for web display, use sRGB<\/b>. On average, it's the closest color space to the average user's average monitor.... on average.\n       Browsers that don't understand the embedded profile are all <a\nhref='\/blog\/photo-tech\/color-spaces-page3\/#ColorStupid'>Color\nStupid<\/a>, so sRGB is the best you can guess.<\/p><\/li>\n\n<\/ol>\n\n<p>If you want to maintain maximum quality and your camera has the ability\nto shoot raw images, do that, converting to <span class='nobr'>a JPG,<\/span> TIFF, or the like when\nneeded, using <span class='nobr'>a color<\/span> space that's appropriate to the intended use (e.g.\nsRGB for the web, or for printing, the color space that best suits your\nprinter). Investigate Apple's <a\nhref='http:\/\/www.apple.com\/aperture\/'>Aperture<\/a> and Adobe's <a\nhref='\/blog\/photo-tech\/lightroom\/'>Lightroom<\/a>. When writing images, be sure each includes an embedded color\nprofile.<\/p>\n\n<p>If you must (or prefer to) shoot JPG in the camera, use AdobeRGB or\nother &#8220;wider&#8221; color space, if available. When making copies for\nthe web, or to give to technically-challenged friends and family, convert <span class='nobr'>a\ncopy<\/span> to sRGB, embed <span class='nobr'>a color<\/span> profile, and use that. When working with the\nimage in an editor like Photoshop, set the &#8220;working space&#8221; to <span class='nobr'>a\ncolor<\/span> space which encompasses both the image's native color space and the\ncolor space you intend to convert to.<\/p>\n\n<p><b><a name='Suggestions2'>Suggestions for the Internet Surfer<\/a><\/b><\/p>\n\n<ol>\n<li><p>Understand the capabilities of your browser\/OS (and perhaps make <span class='nobr'>a change<\/span> if you don't like the limitations).<\/p><\/li>\n<li><p>Even if you don't normally use Apple's <a href='http:\/\/www.apple.com\/safari\/'>Safari<\/a>, consider having it around for the times when you want to see profiled images at their best.<\/p><\/li>\n\n<li><p>Profile your monitor so that you get the most proper colors it has to offer.<\/p><\/li>\n<li><p>Beg Microsoft and Firefox developers to make their browsers color managed.<\/p><\/li>\n<\/ol>\n\n<p><b><a name='Suggestions3'>Suggestions for the Web Designer<\/a><\/b><\/p>\n\n<p>CSS is, by definition, to be rendered with the sRGB color space, but\nthis does not happen on any browser that <span class='nobr'>I know<\/span> of &mdash; for all\npractical purposes, they render CSS colors (and Flash, for that matter)\nwithout color management. <span class='nobr'>On most browsers<\/span>, this is the same treatment as\nimages, but on Safari and other color-managed browsers that respect an\nembedded color profile, be sure to omit the profile if you want your image\ncolors to match your CSS\/Flash colors\n\n<\/p><p>This puts you directly at odds with getting the most proper colors,\nas that requires the embedded profile. Luckily, you can make the decision\non <span class='nobr'>a per<\/span>-image basis:<\/p>\n\n<ul>\n  <li>If you want the image colors to match CSS\/Flash colors: save as sRGB <b>without<\/b> <span class='nobr'>a color<\/span> profile.<\/li>\n  <li>If you want the image colors to look correct: save as sRGB <b>with<\/b> <span class='nobr'>a color<\/span> profile.<\/li>\n<\/ul>\n\n<p>Thus, images that are part of the masthead or nav or other helper images\ncan leave off the color profile, but photographs should keep them.<\/p>\n\n<p><b><a name='Suggestions4'>Suggestions for the Software Developer<\/a><\/b><\/p>\n\n<p>The makes of browsers, image-display applications, image editors, and image-printing applications would do well to...<\/p>\n<ol>\n<li><p>Recognize and apply embedded color profiles.<\/p><\/li>\n\n<li><p>If an image has no profile, but is tagged as sRGB with the\n<tt>EXIF:ColorSpace<\/tt> tag, use sRGB. <span class='nobr'>All digital<\/span> cameras that <span class='nobr'>I know<\/span> of\nwrite sRGB color data without an embedded color profile, but they do note\nsRGB in this Exif field.<\/p><\/li>\n\n<li><p>If no profile and no <tt>ColorSpace<\/tt> field, respond to the\n<tt>InteroperabilityIndex<\/tt> field (&#8220;R98&#8221; for sRGB,\n&#8220;R03&#8221; for AdobeRGB). This is from an Exif-related extension to\nJEITA's DCF (<span class='QO'>&#8220;<\/span>Design rule for Camera File system<span class='QC'>&#8221;<\/span>) standard.\n\n\n<\/p><\/li>\n\n<li><p>If all else fails, use a default color space that is initially sRGB, but allow the user to change it to whatever color space they like.<\/p><\/li>\n<li><p>Educate your users about color-space issues.<\/p><\/li>\n\n<\/ol>\n\n<p>Furthermore, software that writes images....<\/p>\n\n<ul>\n  <li><p>When the color space is sRGB, include the sRGB profile and set the following Exif tags:<\/p>\n<pre>\n    ColorSpace = 1;\n    InteroperabilityIndex = 'R98';\n    InteroperabilityVersion = '0100';\n<\/pre><\/li>\n\n<li><p>When the color space is Adobe RGB, include the Adobe RGB 1998 profile, and set the following Exif tags:<\/p>\n<pre>\n    ColorSpace = 65535;\n    InteroperabilityIndex = 'R03';\n    InteroperabilityVersion = '0100';\n<\/pre><\/li>\n\n<li><p>When the color space is anything else, include the appropriate ICC profile and set the following Exif tags:<\/p>\n<pre>\n    ColorSpace = 65535;\n    delete the InteroperabilityIndex field\n    delete the InteroperabilityVersion field\n<\/pre><\/li>\n<\/ul>\n\n<p>Additionally, when changing the color space of an image, it would be <span class='nobr'>a\ngood<\/span> idea to remove any MakerNotes fields related to the original color\nspace, since they'll no longer apply.<\/p>\n\n<p><b><a name='Suggestions5'>Suggestions for Camera Makers<\/a><\/b><\/p>\n\n<ol>\n<li><p>Embed a color profile in all images your cameras create.<\/p><\/li>\n<li><p>For the time being, continue to default to using sRGB, but offer better color spaces as options.<\/p><\/li>\n<li><p>Offer a color space that preserves as much color data as the camera's sensors originally capture (such as raw).<\/p><\/li>\n<li><p>Educate your users about color-space issues.<\/p><\/li>\n<\/ol>\n\n<p><b><a name='Suggestions6'>Suggestions for Online Image Hosting Services<\/a><\/b><\/p>\n\n<ol>\n<li><p>Add the appropriate color profile to unprofiled images that are tagged with <span class='nobr'>a color<\/span> space name.<\/p><\/li>\n<li><p>Warn users when they upload images that are neither profiled nor tagged with <span class='nobr'>a color<\/span> space name.<\/p><\/li>\n<li><p>When resizing images for thumbnails and such, convert to sRGB and embed <span class='nobr'>a color<\/span> profile.<\/p><\/li>\n<li><p>Educate your users about color-space issues.<\/p><\/li>\n<\/ol>\n\n\n<hr\/>\n\n<p><big><b>Links<\/b><\/big><\/p>\n\n<p>Some related links that I found to be useful...<\/p>\n\n<ul>\n<li>William Steer's <a href='http:\/\/www.techmind.org\/colour\/'>Introduction to Color Science<\/a><\/li>\n<li>Bruce Lindboom's <a href='http:\/\/www.brucelindbloom.com\/index.html?Info.html'>RGB color-space info<\/a> (detailed and technical)<\/li>\n<li>Charles Poynton's <a href='http:\/\/www.poynton.com\/notes\/colour_and_gamma\/ColorFAQ.html'>Color FAQ<\/a> and <a href='http:\/\/www.poynton.com\/notes\/colour_and_gamma\/GammaFAQ.html'>Gamma FAQ<\/a><\/li>\n<li>Eugene Vishnevsky's <a href='http:\/\/www.cs.rit.edu\/~ncs\/color\/'>Introduction to Color<\/a> (<span class='nobr'>a bunch<\/span> of fun Java applets for interactive investigation)<\/li>\n<li>Comparisions of Adobe RGB and ProPhto RGB: <a href='http:\/\/www.outbackphoto.com\/color_management\/cm_06\/essay.html'>one<\/a>,\n     <a href='http:\/\/dimak.blogspot.com\/2005\/07\/practical-side-to-adobergb-versus.html'>two<\/a><\/li>\n<li><a href='http:\/\/www.creativepro.com\/story\/feature\/11132.html'>Color-Science Glossary<\/a><\/li>\n<li><a href='http:\/\/exif.regex.info\/'>Online Exif-Data Viewer<\/a><\/li>\n<li><a href='http:\/\/www.normankoren.com\/color_management.html'>Norman Koren's Introduction to Color Management and Color Science<\/a><\/li>\n<li><a href='http:\/\/www.color.org\/version4html.html'>ICC Profiles: v2 vs. v4<\/a><\/li>\n<li><a href='http:\/\/www.exif.org\/specifications.html'>Copies of JEITA's Exif and DCF standards<\/a><\/li>\n<li><a href='\/blog\/2007-02-17\/384'>More on Digital Color Spaces: <span class='nobr'>a Reply<\/span> to Chris MacAskill<\/a><\/li>\n\n<\/ul>\n\n\n\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"<p><b>Perfect Colors?<\/b><\/p> <p>Okay, so let's say that you have an image file with an embedded color profile, a properly-profiled monitor, and an application that respects both profiles: will you finally see the proper, true colors? <\/p><p> Maybe. <\/p><p> First, you must define \"true color.\" If you define it as the colors as encoded in the image, then you'll see them properly to the extent that your monitor can actually display the image's full range of colors. A monitor or printer can only produce the colors, that, er, it has the physical ability to produce. If it's a particularly wide color [...]","protected":false},"author":1,"featured_media":0,"parent":251,"menu_order":7,"comment_status":"open","ping_status":"open","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/pages\/261"}],"collection":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/comments?post=261"}],"version-history":[{"count":0,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/pages\/261\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/pages\/251"}],"wp:attachment":[{"href":"https:\/\/regex.info\/blog\/wp-json\/wp\/v2\/media?parent=261"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}