Colour Management and the World Wide Web

© Phil Tanner

If this image appears in your browser as a ‘negative image’ your browser is not colour managed. Read on for the solution…

Compare the image below in both Firefox and Internet Explorer!

Colour Management Test
Unlike good ole Photoshop, the World Wide Web is not a

Colour Managed environment

. This means that the colours we see in an image when surfing the Net are basically arbitrary. OK the Net does have a de facto colour space associated with it being sRGB and ‘colour savvy’ web publishers have historically converted image colours to the sRGB colour space.

While this is a pragmatic approach it is far from ideal. For starters sRGB (developed by Hewlett Packard and Microsoft in 1996) was intended to reflect the colour palette of a CRT monitor which very few people use today.

Furthermore most web browsers haven't been

Colour Managed

so they have neither been respecting nor enforcing the sRGB colour space. All they do in effect is pump the raw RGB data to the monitor.

With the advent of “wide gamut” (wider than sRGB) LCD monitors the lack of colour management in the browser is the primary cause of the dreaded over saturated skin tones and red colour casts that are so frequently mentioned in photography forums. In this age of LCD a

Colour Managed Browser

is in my opinion essential.

Thankfully Mozilla have been on the case and Mozilla Firefox is now wonderfully colour managed by default. Sadly Internet Explorer is still not properly colour managed.

If you don’t already have Firefox on your system I highly recommend it. Download Firefox for free

What a difference colour management can make!

For all the photographers out there who correctly calibrate their monitors, Firefox has some excellent expert features. It can be configured to use a specific display icc profile, respect only embedded icc profiles or colour manage all images (sRGB is assumed where a profile is not embedded). You can even select your preferred rendering intent. There is a plugin for amending these settings but personally I’m happy to delve right into the program configuration area.

Colour Management in Mozilla Firefox (advanced configuration)

By default Firefox loads the following colour management settings: The key change I recommend making is changing the colour management mode so that all images are colour managed. I will detail the procedure here and there is a table at the foot of this article explaining the various other colour management settings that can be made if you so wish.

In the URL address bar at the top of the Firefox browser window type about:config and press enter.

You will get a warning about changing advanced settings.To proceed click the “I’ll be careful, I promise!” button

In the Filter text box type color_management which will isolate the 3 settings we are interested in. DoubleClick the item labled gfx.color_management.mode which will bring up a dialogue box. Replace the number in the dialogue box with a number 1 and Click OK.

Finally close and restart the browser and your new settings are now in effect.

Colour Management settings in Firefox

Setting Name Possible Settings Effect of each setting
gfx.color_management.display_profile Path to display profile e.g. C:\WINDOWS\system32\
Sets the specific display profile to be used
Nothing (default) Default system display profile will be used.
gfx.color_management.mode   0 Disable Colour Management

  1 Colour Manage all graphics
(assume images without an embedded icc profile are in sRGB colour space)

  2 (default) Only colour manage graphics with embedded icc profiles
gfx.color_management.rendering_intent   -1 Use intent specified in embedded icc profiles
  0 (default) Perceptual

  1 Relative Colorimetric

  2 Saturation

  3 Absolute Colorimetric