sRGB, Color Lumens, and Calibrating Projectors Posted on August 10, 2015 By Art Feierman 1. sRGB, Color Lumens, and Calibrating Projectors - Some History on sRGB - The Color Lumens Standard Revisited2. sRGB, Color Lumens, and Calibrating Projectors 2 - Sports! - The Bottom Line With a number of new sRGB single chip DLP projectors hitting the market, I’ve been asked in a number of emails, questions about overall picture quality, as people are trying to sort out what being an sRGB projector means, or a projector with high Color lumens means, especially from a competitive standpoint. I’ve previously written often about about and done a video relating to “color lumens.” In reality, my first mention discussing the issue of color lumens was back in 2003, but that was long before the term “color lumens” was being used, or the color lumens standard was created. Surprise, sRGB projectors also go back to at least 2003! Some History on sRGBThat’s right, although probably a big surprise to many of you who are just hearing about sRGB in the last few months, sRGB has been around for a long, long time. I’m not sure when the first projector appeared with an sRGB mode, but Epson’s very first serious home theater projector, the TW100 offered an sRGB mode way back in 2003. For those curious, I even found an old Epson press release on our favorite competitive website: http://www.projectorcentral.com/news_story_407.htm So, if sRGB isn’t something new and wonderful, what exactly is it, and does it play nicely with color lumens and with calibrating projectors. Not being an engineer, I’m really not overly familiar with the technical aspects of sRGB but I can tell you that what I remember from “back in the day.” sRGB was created in the heyday of the PC as a solution for computer monitors, and online vendors. The web was going through the rapid expansion of the web as a place to buy products. There was a huge problem. You might log into a department store website (or Amazon), looking for a shirt, sweater, see one you like (or several) and order it. Your package arrives, and the vibrant red you saw on your computer screen doesn’t show up, instead the shirt proves to be an orange red that arrives. It’s not the wrong shirt, it’s just that your computer screen didn’t show the color correctly. Bummer. So along comes sRGB. The idea is that if your computer monitor has an sRGB mode, and the online seller supports an sRGB matched output, then you should see the same color on the screen as the clothes when it is delivered. Now I can’t tell you how it played out, as I never really followed it, other than to say it never really caught on mainstream. sRGB exists on many computer monitors, but typically being a less bright, and relatively muted looking image, few use it. Still the concept was a good one, establishing a standard for matching color. Now why does that sound familiar? There are standards for other things – notably, in our case, for having HDTVs and projectors produce the correct color that matches what is the color of original film, etc,. You probably know a few of these standards by name. D65, and REC709. And we’re all hoping that with Blu-ray UHD we’ll finally get the DCI standard that’s used for the movie theaters. For movies and TV these standards set color temp for 6500 Kelvin, Well, seems so does sRGB. As a result, while a different standard, it’s relatively close. OK, with all of that in mind, it’s time to answer the big question? What does a projector having sRGB really mean? Simply stated it means that a projector that meets this standard has the ability to produce excellent color. The important aspect is that it needs to meet the sRGB standard, not just claim it does. Test image – sRGB mode (BenQ HC1200) You may be interested to learn that the folks at Technicolor are certifying projectors’ color. They make the same point I’m trying to make: That a manufacturer claims that their mode is sRGB is not the same as actually delivering a mode that meets all the sRGB requirements. A typical Cinema mode (BenQ HC1200) Just keep in mind that almost any respectable projector can be calibrated. Some very low end ones don’t offer the necessary controls, but the majority do, both home and business projectors alike. The Color Lumens Standard RevisitedA few years ago a Color Lumens standard was created by a reputable standards group. This is a very different thing as it’s not a standard that determines how color is represented, but it’s a standard for measuring how much color there is to work with. The creation of a color standard was motivated by techniques used by projector companies that wanted to have the highest possible lumen claims. It is possible to produce a projector with lots of white lumens, but poor on color. Of course the typical consumer tends to be impressed by who’s got the most lumens, just as stereo buyers always focused on how many watts, or before our quest of economy and clean air, many looked at how much horsepower a car had as the important spec. Business 3LCD projector in Theatre mode Business 3LCD projector – sRGB mode As with the sRGB vs Cinema on the BenQ HC1200 in the pair further up the page, here’s a different image taken a while back with a business/education 3LCD projector (definitely not home theater). Again, the two modes are very similar. Is sRGB better than the other mode in both cases. Can’t tell without measuring, but obviously they are all very close. Based on that, consider sRGB as another “best” mode to choose from, but not necessarily the best. More on page 2!