Hack #31. Properly Size Your HD Image

Once you've got your HD signal coming in, you'll need to ensure that it appears properly on your television set. Otherwise, you'll miss important detail and lessen the HD experience.

Many are the stories of a consumer buying an expensive HD-ready wide-screen TV [Hack #29] , spending hundreds on killer programming [Hack #28] , and still seeing only 70% or 80% of the overall image. The choice seems to be between black bars on the side [Hack #13] or an image that clearly extends below the bottom of the screen and above the top. Some careful tweaking can take care of this once and for all.

HD programming needs to form an exact 16 x 9 image, form-fitted to your TV's 16 x 9 screen. Unfortunately, this almost never is set up for you out of the box. RPTVs are overscanned quite heavily from the factory, meaning you are missing substantial parts of your picture. This process of reducing the overscan is not for the faint of heart, however, because doing so hoses your geometry and convergence, all of which have to be totally recalibrated [Hack #62] afterward.

You'll need to enter your television's service menu, and then manually set both the vertical and horizontal size.

Tip

As always, when dealing with service menus, write down everything before changing anything.

When you've found the menu options you want, load up a true HD image. You can usually get one of these by setting your set top box [Hack #30] to PBS or HDNet; both channels have true HD broadcasts most of the day. Then, as the broadcast is showing, squeeze in the edges of the screen vertically until you can just see the edges of the picture on the top and bottom of your TV. Then you can just nudge the size back up, and you're all set. Repeat the same process horizontally: squeeze in, and then set the overscan.

As you're setting the size, you might find that the picture is also off-center. You can see this is happening when one side of the picture is flush with the edge of the display on your set, but the other side is not. You'll have to move the image toward the side that shows the extra edge and then resize again. This is a trial-and-error process, and can take some time.

Tip

For those of you used to working with computer monitors, this is the same way you ensure your monitor is displaying all of the video image and not cutting some off (or leaving wasted display space along an edge).

If you're having trouble getting the edges aligned, focus on the center of the edge you're working on; in other words, don't worry about the corners. When you rework the convergence and geometry of your screen via calibration, these corners will take care of themselves.

Finally, with the picture just where you want it, you'll have to go back to calibration, working on the color levels, convergence, and the like. This can be a lengthy process; the more the screen is off when you get it, the larger the error your adjustments can cause. Still, it's well worth it to see all of the image you're working with rather than just part of it.

—Robert Jones, Image Perfection

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