Different television sizes will offer different advantages. Factors to consider when considering screen size include the type of content being consumed, the size of the room you'll be installing the television in and cost. No single factor should be the basis of comparison for screen size, as different factors can affect the quality or usefulness in different ways.
Cathode Ray Tube vs. Flat Panel
For decades, televisions used cathode ray tube (CRT) technology; these were the boxy TVs many of us grew up watching. There were other variations, but the CRT was the standard. These televisions had a vertical to horizontal ratio of 4:3, which was the standard used by most television shows. This wasn't ideal for most movies, however, as they were often shot on a wider ratio, such as 16:9. This led to displaying films on TV stations or videotapes in either a widescreen format, meaning the top and bottom of the picture would be black to show the full width of the film, or using a technique called pan and scan, which would adjust the picture as needed to reveal elements of the film that might be hidden by the narrower screen. In the past decade, flat panel TVs using liquid crystal display (LCD) and plasma technologies have dominated the market. These new units are often manufactured as widescreen TVs, allowing better viewing of films in their original formats. The new technology has also allowed for larger screen sizes to be manufactured cheaper, putting very large TVs within a reasonable price range for consumers.
Replacing a CRT
The difference in ratios between a old-style CRT and the more modern LCDs and plasmas should be noted if replacing an old TV. A commonly advertised measurement for screen size is the diagonal length. When purchasing a 32-inch TV, you are purchasing a television with a 32-inch diagonal length. What should be noted is a 32-inch CRT television is not the same size as a 32-inch widescreen flat panel LCD or plasma. A 32-inch flat panel TV will typically be shorter than a 32-inch CRT. Due to these differences, even the overall screen area is smaller on a 32-inch flat panel. To get the same screen area, multiply the size of the CRT by 1.06 to find out the flat panel size you need. This will still be a shorter TV, so if you prefer a television of the same height, multiply the diagonal length of your old TV by 1.22 to find the size you need.
The type of content you'll be consuming on a television should be a determining factor in comparing screen sizes. If you're looking at primarily older content, old DVDs or even VHS tapes, a larger screen is unnecessary and may even be a negative. The larger the screen, the more detail you are viewing. Lower-quality content will show up poorly on a larger screen because of the amount of detail you can see. If, on the other hand, you have high-quality content, HD TV channels or Blu-ray movies, a larger TV will be beneficial. With higher-quality content and a small TV, you won't see the same level of detail as is available in the content.
Room size is an important factor in comparing television sizes. The larger the room and larger the distance between the TV and the farthest person watching it, the larger the screen should be. A large TV in a small room is overkill, and at closer distances, you may not even be able to view the whole picture. There are ideal distance ranges suggested by manufacturers for different sizes of TVs. For example, a 26-inch screen has an ideal viewing distance of 3.3 to 6.5 feet. A 65-inch screen has an ideal viewing distance of 8.1 to 16.2 feet. Generally, the ideal viewing distance is between 1.5 and 3 times the screen's diagonal measure.
In comparing screen sizes, cost is a factor. The larger the screen, the more expensive the TV. It's a point to be weighed in the comparison. For example, if comparing a 55-inch and 65-inch TV that will be displaying high-quality content at a distance of 10 feet from the viewer, the overall experience of watching the TVs is comparable. It's comfortably within the optimum viewing distance range for both sizes, and both sizes will offer a detailed experience of high-quality content. The main difference between these comes down to cost. A 65-inch TV could cost almost twice as much as a 55-inch model.