Display Types » CRT RPTV $375

When I started calibrating, rear projection TVs (RPTVs) made up the majority of calibration jobs, and no wonder... There's so much potential waiting to be unleashed! All CRT RPTVs benefit greatly from an ISF calibration. Many times, getting your CRT RPTV calibrated can be such an improvement that the urge to upgrade to one of the latest technologies will be significantly reduced or eliminated.

The first order of business when I get to your house is to document and measure the current settings of your display, and also evaluate the viewing environment, cabling, and source equipment settings.

The CRTs have both electrical and mechanical focus controls. The focus is often improved with calibration, and sometimes the difference is dramatic!

CRT based RPTVs have to throw red, green, and blue light on top of one another on to the screen in order to make a picture. What happens if the blue or red doesn't line up with the green? The picture develops some pretty serious nasties, that's what! Whenever possible, I'll get in the service menu and make adjustments to the convergence that might not have been made user adjustable by the manufacturer. I take my time to do it right; 3 passes is the norm.

The best way to get a CRT's picture perfectly straight and linear is with a geometry template. The template is drawn on a clear plastic mat and attached to the TV's protective screen. When templates are available for that model, I get into the service menu and shape and bend the TV's self-generated lines until they track what is on the template. If no template is readily available for that model or size, I use a tape measure and adjust geometry by eye. Wow, it's surprising how far off these sets can be!

Next up is finding the proper settings for the standard brightness, contrast, sharpness, color, and tint. If possible, I'll adjust them so that the default setting of the user control is the correct setting. When possible, I'll also make adjustments to the gamma, color decoder (eliminating red push), DC restoration, scan velocity modulation, chroma delay, and dynamic picture/color controls. Some manufacturers make all these things adjustable in the service menu, but others might not have an adjustment for everything. For example, Brand X might have adjustments for everything except the color decoder- which means that we'll just have to make do as best as we can without that adjustment.

Now we come to the heart of the matter- gray scale tracking. Very few TVs have a properly calibrated gray scale, due in part to sloppy or time restricted manufacturing and a desire for the image to scream at you on the brightly lit showroom floor. Poor gray scale performance can result in a colored tint to dark areas of the picture in addition to the inability to look natural no matter how the color and tint are set. Using a color analyzer, I'll adjust it as close as possible to the video standard of D6500. Many times, this is a tedious balancing act that might take hours. Many display's gray scales track very well from dim to bright, but with a few there may be problems getting the red, green, and blue to track closely. However, even with sets that do not track particularly well, there is much room for improvement.

Finally, I'll go back and fine tune all the controls. Then it's time to evaluate the picture! In a few situations, your display might look more subdued than before calibration, but vibrant colors and more lifelike details will come shining through. Picture problems like excessive shimmering, bent lines, chronically sun burnt flesh tones, washed out images, and colored shadows will be greatly reduced or eliminated.

The time it takes to do a calibration depends on your display and how easy and complete it's service menu is. An average CRT RPTV calibration usually takes about 6-10 hours. Some older displays might not have a service menu, in which case I will have to take the back off and adjust trim pots. This does not normally take more time, but it might mean that the display will have to be moved. Do I mind if owners watch me do a calibration? Usually not- in fact, it's great to be able to explain what I'm doing; but there will be some long, boring time lapses (some with all the lights off), so have a laptop or something else handy! If something has been really messed up on your TV, or if someone got into something they shouldn't have, please warn me ahead of time.

Many people have wondered if performing an ISF calibration will make all displays look more or less the same. The reality is that while a calibration will get the most out of your display, there will still be significant performance differences. It's somewhat like the differences between 2 different speakers after they have both been equalized and optimally placed in a room.

The grayscale, color decoder, and other tweaks combine to make a significant improvement in the enjoyment of your set.  I've calibrated nearly all brands, including Toshiba, Mitsubishi, Sony, Pioneer, Hitachi, Philips/Magnavox, Samsung, Panasonic, RCA, Zenith, and others.

Note: Not all procedures are available or necessary on every set.

ISF calibration: $375

• lens cleaning - much like an ionic air purifier, your TV is a dust magnet, creates a hazy/clouded image as dust builds up on the lens
• mechanical focus - twisting the lens, similar to focusing binoculars or a telescope, yielding a sharper picture
• electrostatic focus - ensures the smallest beam size or dot pitch possible, increasing apparent resolution
• geometry with template when possible - straightens TV picture, eliminating "speed bumps", correctly proportions images, and reduces overscan
• service level convergence - tightening overlap of red, green, and blue, eliminating color fringing and improving color definition
• lens striping if needed and requested - improves color uniformity from edge to edge (from left to right) across screen
• color decoding - eliminates "red push", chronic sunburn, calibrate hue & saturation of red, green, and blue individually
• gamma adjustment - brightness ratio defining how bright the middle picture level is in relation to the peak brightness and dark shadows
• brightness stability - brightness locked in place with different average picture levels, bright scenes won't lose shadow detail
• reduce edge enhancement - gives picture much more natural appearance, reduces glowing around lines and objects
• center user controls - resetting user controls reverts to calibrated settings
• grayscale - foundation for accurate color reproduction, eliminating improper color tints in the grayscale, white will look white, black will look black, and gray will....well, you get the point
• all used inputs/scanrates calibrated - many TVs require separate calibration for different types of inputs, i.e. component, HDMI/DVI, 480p vs. 1080i scanrates