The main difference between NTSC and PAL is the speed at which a broadcast is displayed on a TV screen. NTSC displays at 30 frames per second (fps), while PAL provides 25 fps.
Most countries in North and South America, including the United States and Canada, use the National Television Standards Committee (NTSC) format, while Europe, Australia, and parts of Asia use a concurrent format called Phase Alternating Line (PAL).
Each format also uses a different number of lines on an old analog TV display when it shows the signal, creating two different resolutions. The widespread adoption of high-definition televisions (HDTVs) by many consumers has not eliminated this difference, however, as previous transmission methods have affected the reproduction of digital signal.
Differences between NTSC and PAL power systems
The differences between these formats really start with the power supply system behind the transmissions displayed on a TV.
In the United States and in countries like Canada and Mexico, electricity is generated at 60 hertz, so for technical reasons the NTSC signal is also sent at 60 “fields” per second. The first field takes into account all odd lines on one screen, while the second includes even rows. Since most analog TVs use an interlaced system, this means that 30 fields of one type are sent, along with 30 fields of the other type every second.
This alternation of lines occurs so fast that it is not detectable by the human eye, just like a film that flows through a projector. The result for an NTSC TV is 30 frames of a full image, consisting of two fields for each frame, which appear every second. Since countries in Europe and Asia often use 50 hertz power, equivalent PAL lines come out at 50 fields per second. This means that a PAL signal is displayed at 25 fps, consisting of two sets of 25 alternating lines.
PAL vs NTSC: Which is the best?
Another difference between NTSC and PAL formats is the quality of the resolution. More lines usually mean more visual information, which results in better image quality and resolution. Although PAL may have fewer frames per second, it displays more rows than NTSC. PAL TV broadcasts contain 625 lines of resolution, from top to bottom, compared to 525 of NTSC.
When an NTSC video tape is converted to PAL, black bars are often used to compensate for the smaller appearance of the screen, just like the bars at the top and bottom of a mailbox or a widescreen movie.
PAL and NTSC color signals
When the NTSC format was first adopted in 1941, little was discussed about color transmissions. With the development of color television technology, however, engineers had to create a transmission method that would still allow owners of monochrome televisions to receive an image.
The PAL system, on the other hand, was created after the advent of color transmission, so the color signals are much more faithful to the original image. This distinction often means that an unconverted signal played on a TV of the other format might appear in black and white, rather than color.
Can I convert NTSC to PAL?
Yes. A European TV may not work properly in the U.S. and an NTSC video typically does not play on a PAL device. To resolve this issue, there are a number of companies offering conversion kits from one format to another. Some of these conversion methods can take a long time and vary in terms of quality, although there are companies that provide paid conversion services.
If a PAL movie is converted to an NTSC tape, 5 extra frames per second must be added or the action looks ‘syshot’. The opposite is true for an NTSC movie converted to PAL; five frames must be removed per second or the movement can become unnaturally slow. Since audio and video data are often connected, you may also need to speed up or slow down the audio signal to get a correct sound during playback.
Is NTSC PAL more important?
While the transition from analog to digital and HD TVs was an opportunity to move away from old formats, some limitations remain. TVs have yet to display an image based on a certain number of frames per second, and so many HD TVs in the United States or Europe continue to be displayed at 30 or 25 fps.
The improvement, however, is that these devices are often customizable and an HDTV may be able to broadcast in both formats and work properly in any area. It all depends on the features of a particular TV model and the options available in its configuration menu.
Can I use a PAL camera in the United States?
Sometimes. More often, the latest media player hardware is designed to work with one format or another to work properly with various TVs, although technically it may be able to use both. DVDs and Blu-rayTM, however, are generally encoded by region, which means they only work with players in a given area.
A DVD encoded for Region 1, which includes the United States and Canada, usually does not work in a DVD player from Germany, which is located in Region 2. Media and ‘regionless’ players can eliminate this issue, although these devices and disks are not commonly available.
In the past, Video Home System (VHS) tapes were limited to NTSC or PAL playback, while newer digital formats such as DVD and Blu-rayTM do not have this limitation.
Author: Angelo Raguso
