Dynamic Contrast Ratio

Plasma HDTV - The Best Technology Gives the Best Picture

Only two things are truly important when shopping for a plasma hdtv. Everything else is nice to have. Read on to find out what you need, and what you can ignore.

Anyone who wants to get the best picture quality in a mainstream HDTV regardless of price will be looking at a plasma HDTV and nothing else. It is superior to both its main competitors in the HDTV space, DLP and LCD, both in the technology used and in picture quality. Perhaps the nicest thing about buying a plasma HDTV is that it is actually easier to buy than the other technologies, with fewer variables to consider.

A Quick Overview of Plasma HDTV Technology

An in-depth look at the technology behind plasma HDTV technology could fill a large (and boring) book. The summary of the tech goes like this: millions of tiny fluorescent lights of various colors, called cells, are sandwiched between two glass plates. Between the lights and the rear glass plate are electrodes which deliver electricity to light up the cells. Lighting certain cells to a desired brightness and in the correct order creates color and the illusion of movement. This is a gross over-simplification, of course, but is enough for our purposes.

Advantages of Plasma HDTV

The biggest advantage of a plasma HDTV over its competitors is its flatness. Plasma is absolutely the skinniest HDTV technology available, making it ideal for wall-mounting and other utilization where space is an issue. Conversely, plasma HDTV is also the largest available, aside from projectors, with mainstream models currently topping out at around 65" while mainstream LCD HDTVs stop at around 52". Plasma HDTVs also avoid the ghosting and tearing issues frequently found in DLP and LCD models.

Shortcomings of Plasma HDTV

Plasma HDTV units are subject to screen burn-in. What this means is that if the same static image is displayed for a long period of time, the image can become somewhat "stuck" on the screen. For 99% of home users, this will not be a problem, but if your favorite station is CNN Headline News or a similar station with a lot of static content and you leave it on all day, you will actually be better off with an LCD HDTV. Plasma's other big disadvantage is that running it at maximum brightness will significantly reduce the lifetime of the panel. Because of this, many plasma HDTV owners leave the brightness settings well below maximum, which still gives it a brighter display than a conventional CRT television.

What to Look for When Shopping for a Plasma HDTV

Aside from size and price, there are really only two determining factors that must be taken into account when looking at plasma HDTVs: resolution and contrast ratio.

Resolution is determined by the number of cells that the plasma HDTV display physically consists of. It is different than the display capability, which is often what is listed. The resolution of the best plasma HDTVs is 1920 x 1080, and this is the number you want to aim for, because this is the only way to see 1080p content at its maximum resolution. Many plasma HDTVs have a resolution of only 1366 x 768 or lower; this means that even if a unit is listed as "capable" of displaying 1080p content, it will actually be down-sampling it to 720p to fit on its screen, which will result in a lower-quality image.

Contrast ratio is one of the most important numbers used in marketing HDTVs, which means that manufacturers have come up with all sorts of strange, tricky ways of "measuring" the contrast ratio in a way that proves their unit has a higher contrast ratio than their competitors. Now, higher numbers in contrast ratio always mean better, sharper pictures, but some manufacturers (especially manufacturers of LCD HDTVs) are using what is termed "dynamic" contrast ratio, showing numbers as ridiculously high as 20, 000:1. "Static" or "true" contrast ratios give the truer indication of how sharp a picture will be, but the key is to compare the same contrast ratio when looking at plasma HDTVs. Compare the Dynamic Contrast Ratio of two units against each other, or the static contrast ratio, but do not compare the Dynamic Contrast Ratio of one unit to the static contrast ratio of another. By way of comparison, a clean print of a movie at a typical theater has a static contrast ratio of around 500:1.

After investigating the resolution and contrast ratio of the units you are looking at, everything else, such as picture-in-picture, number of inputs, built-in program guide, and of course the warranty, are the "nice-to-haves" which will let you determine exactly which plasma HDTV is the best for you.