calibration

At CNET we've recently made some much-needed tweaks to our TV testing procedure for 2011, including the addition of complete calibration charts and a mostly new Geek Box with results of our measurements of TVs. The new review format debuted with the Samsung UND6400 review we posted earlier this week; scroll down to the bottom of this page for a peek.

A few of the new measurements we now publish include black level, primary color luminance level, and color of gray in very dark areas. The charts, courtesy of Spectracal's respected Calman 4.2 software, take it a step further, showing at-a-glance grayscale, color, and gamma information both before and after calibration.

Owners of the TV can try out our detailed picture settings, which we still publish with every review, if they want to get close to our calibration.

If you're interested in learning more, we've also updated our comprehensive How We Test document, which goes into plenty of detail about the tests and the logic behind them. And as always, we welcome your comments on TV testing and TV reviews in general.

Read the How We Test: TVs or check out the video below for more.… Read more

One of my recommendations whenever anyone gets a new computer or more specifically a new monitor is to calibrate the display so colors appear properly and as expected. This will not only allow you to adjust the richness of the colors on screen, but also allow you to have the colors appear uniformly across different monitors and output devices, which can be especially useful if your work involves design, photography, or otherwise depends on proper color matching.

What is color calibration?

Calibrating a display is essentially adjusting the output for the individual colors (red, green, blue) across various light intensity … Read more

MacFixIt Answers is a feature in which we answer questions e-mailed from our readers. This week, we have questions about old e-mail addresses still being used in Mail's address auto-completion, battery calibration behavior in MacBook Pro systems, printer queue accidentally removed from the Dock, and a commend on another useful utility that tracks file system changes.

Question: Old e-mail addresses still being used in Mail's address auto-completion

MacFixIt reader "Charles" asks:

I have a problem with Mail/Address Book. When my friends change their e-mail address, the old address remains in my system. When I send … Read more

Just about every home theater receiver comes with an automatic speaker setup and calibration system: Denon, Marantz, and Onkyo feature Audyssey; Pioneer has MCACC (multichannel acoustic calibration); Sony's is called DCAC (digital cinema auto calibration); and Yamaha's proprietary system goes by the name YPAO (Yamaha Parametric Room Acoustic Optimizer). The systems handle the basics like determining the sizes of all the speakers, setting speaker and subwoofer volume levels and the speaker-subwoofer crossover point, measuring the distances from the speakers to the listener, and checking that all of the speaker cables are correctly hooked up. Some autosetup systems also employ equalization to balance the frequency response of all the speakers, and they try to minimize room acoustic problems.

To accomplish these goals, the systems send test tones through all of the speakers and the subwoofer, and they all use a microphone to capture the sounds of the speakers. Autosetup is a great idea, but there's no guarantee you'll have a perfectly adjusted home theater sound after the test tones have run through all of their beeps, whooshes, and thumps. The volume levels of the speakers may not be perfectly adjusted, the speaker-to-listener distances may be inaccurate, and the subwoofer volume may be too loud or too low. In the worst cases, the autosetup sounds worse than doing no setup at all.

These malfunctions can be caused by a number of things: your room may not be quiet enough, microphone placement can have an effect, or your subwoofer's built-in volume control may be set too low or too high. I'd recommend checking that all of the speakers are wired "in-phase," meaning red/+ and black/- connections are consistent at the speaker and receiver ends. Some autosetup systems check the wiring, but try to get it right in the first place.

I recently met with Chris Kyriakakis, Audyssey's CTO and founder, to talk about new developments at Audyssey, and while I had his ear, I brought up my concerns about autosetup problems. He followed up with a list of tips that generally apply to most autosetup systems. There's a lot of useful information about Audyssey setup on the company's Web site.… Read more

Lutcurve is a sophisticated display calibration tool that can optimize your LCD or CRT monitor's settings. It's easy to use, but we agree with developer Atrise's recommendation that new users first read the PDF-based manual that comes with the download. It explains not only how to use the software but also what it does and why, so you get a good lesson in how your computer's monitor creates realistic displays.

Lutcurve's main window features a Command Button Bar along the bottom that includes Navigation Tabs accessing its calibration features. The program changes your monitor's … Read more

Get the most out of your computer's LCD monitor with some simple adjustments. In this video, CNET editor Eric Franklin walks you through the process.

MacFixIt Answers is a feature from MacFixIt in which we answer questions e-mailed to us by our readers. We have been getting many questions from our readers, and we hope to share our correspondence so everyone may benefit from and contribute to them. This week we have questions about monitor calibration with multiple graphics cards, window minimization options, screen zooming, and question mark symbols at bootup.… Read more

Calibre provides all the elements you need to organize and manage an e-book collection. With a simple set of tools and a helpful layout, this program is a nice choice for any electronic reading lover.

The program's interface is a snap to understand because of its professionally designed layout and easy-to-use command icons. Calibre lets you open a variety of e-book types and read them. You download your e-books from your desktop or hard drive directly into Calibre. The entire process is so simple that we never felt the need to consult the Help file. You can easily sort … Read more

Auto speaker setup and calibration is a popular feature on almost every receiver and a lot of home-theater-in-a-box systems.

Sure, it sounds like a peachy idea, but the accuracy of auto setup is hardly a sure thing; and at their worst, auto setup systems sound worse than no setup at all.

Ideally, the setup system automatically determines speaker sizes (large or small), measures speaker-to-listener distances, sets the volume levels of all of the speakers, determines the proper subwoofer volume level, checks that all the speaker wires' "+" and "-" connections are properly oriented at the speaker and receiver ends, and calculates the subwoofer-to-speaker crossover point. Some receivers also employ EQ (equalization) curves to correct for speaker and room acoustic anomalies.

What's not to like? Well, it the auto setup worked perfectly, nothing.

But they're mostly flawed: Subwoofer calibrations are almost always off. Auto calibration systems boost the sub volume much too high, and overestimate the sub distance to the listener by a factor of two (so a 10 foot distance becomes 20 or more feet).

Worse yet, auto setup systems rarely set the subwoofer-to-satellite speakers crossover frequency to the optimum point. That is, they tend to set the crossover too high, say 150 Hertz, which unnecessarily restricts the speakers' bass response. The speakers might sound better with a lower crossover setting. I recommend 80Hz for all speakers with 4- to 6-inch woofers; 100Hz for 3-inch woofers; and higher settings of 120Hz or 150Hz only for the tiniest speakers.

Accessing the measurement data post auto setup can be tricky on some receivers. Then you really don't know what you have.

Thing is, manual setup isn't all that difficult and will likely be more accurate. And chances are you wouldn't muck up the distances as poorly as the autosetup would. Running the test tones over the speakers and manually adjusting the sound by ear or with a Radio Shack meter isn't so hard to do.… Read more