Color Management: Part 5 - The World Wide Web
This is an interesting problem. To date, we’ve been talking about standards and the goodness of standards. We’ve even talked about how if you and your clients have standards, you can see images the same way even though you’re thousands of miles apart. What about if your post your image on the web. How will Joe Average Guy see your images? That’s a big unknown.
One of the things you’ll find is the web is essentially unregulated in this respect. You have very little control over what tools Joe Average Guy will use to view your image on the web. Fortunately, there was an attempt to apply a few standards when the web was essentially brand new. Microsoft in its infinite global wisdom decided to use a fairly narrow color space as its standard. It’s called sRGB. This standard migrated to become the standard color space for most web utilities. Because Windows is so common throughout the world most computer users have web browsers designed to render images in this fairly narrow color space. As a result, images on the web that use a broad color space like Adobe 98 aren’t rendered correctly when viewed on standard Windows web browsers. In fact, they’ll look muddy or have jagged transitions between tonal qualities. For the color fanatic like you all are now, this is clearly not acceptable.
What are you going to do? Instead of letting some anonymous web browser do who knows what color translating, you should do it for them. You need to convert the images you post on the web to the sRGB color space. Through this process you can control how the images appear and therefore control how they’ll look on Joe Average’s computer. Adobe Photoshop has a very useful applet call Save For Web. Through a couple of clicks, you can define how the translation will occur and even preview the translation. It’s all very simple. When you’re done, that’s the image you need to upload to the web for general view by everyone.
I’ll even add that if you don’t know your client has your color space, it’s highly likely they can see things using sRGB. So, when you don’t know it’s the best compromise to send to your clients image files based on sRGB color space.
What about Mac users out there? To make things complicated, Apple decided to present it’s images using a different gamma than everyone else. That means images tuned for the Mac environment will not look correct in the Windows world without the proper color space. If you posted your image from a Mac on the web without a color space imbedded, it will not look right when it finally is seen on the Windows machine. So, you need to post your mac images with sRGB color space. What about the other way around? What about when a Windows user sends a Mac user an image? Fortunately, Macs are typically more color aware than Windows machines. First, all Macs are color space savvy and look for imbedded color space profiles in image files. When a Mac sees the profile, it does the necessary conversions to make sure that image looks as good on the Mac as it did on the Windows machine. This means images that you tune for the web using sRGB color space will be rendered correctly by your Mac because it reads and interprets correctly the color space information.
All this work to get your web images posted with the right color space will not guarantee your images will look right on anyone’s computer. Most folks do not have calibrated monitors. Without a properly calibrated monitor, they will not see your images in all the glory you worked so hard to control.
That my friend is life.
If you’re doing everything I’ve talked about in this article, you’ve done everything you can possibly do. One thing you can’t do is go into everyone’s house to make sure they have a calibrated monitor and they’ve setup their system to properly view profiled images. Having people out there with less than perfect image viewing machines is just the way it is.
That’s about it. The whole color thing explained in simple terms. I haven’t shown a single graph or drawn out a single match equation. All of this is pretty simple. If you have questions, drop me a line.
Cheers
Tom