Not knowing anything about NTSC and PAL does not make a big difference in the life of a common man. These are acronyms for television encoding systems and NTSC and PAL are two systems that are dominating the world at the moment. These systems are meant for broadcast engineers and which country uses NTSC or PAL is dependent upon the frequency of electric supply used by it. The differences between NTSC and PAL will be clear to the readers after reading this article.
In US and other American countries, electricity supply is at 60Hz, which implies that NTSC signal is also sent at 60fps. What this means is that 30 images are sent out per second followed by 30 intermittent lines. However, the frame rate is so high that the human eye is unable to catch any alteration and one sees uninterrupted image as if a film is running on a projector. So if you have an NTSC TV set, you are getting 30 images per second.
In Europe, electricity supply is 50Hz so, the PAL lines are sent at 50 lines per second, or in effect 25 images per second. This implies 5 frames per second less than in NTSC. So, if you are watching a program made in NTSC on PAL, you would find that because of lesser frames per second, motion appears to be a bit distorted as was the case in silent movies, where characters appeared to be doing things faster. Watching PAL movies in NTSC produce a contrasting effect and makes the action look slower than it is.
However, this is not the only difference in NTSC and PAL; there are also differences in clarity of the image. Though there are 5 frames per second less in PAL, there are more lines of resolution than in NTSC. Whereas, there are 625 lines of resolution in PAL broadcast, there are only 525 in case of NTSC broadcast. Higher resolution obviously results in higher picture clarity in PAL. NTSC system is older than PAL and was in place when B/W broadcasting was in vogue. Broadcasters had to make many changes when color broadcasting appeared on the scene. PAL was developed later and so it is considered more suitable for color broadcast. When a program made in NTSC is to be formatted for PAL, one can see black bars at the top and bottom that are used to fill up empty spaces.
DVD’s are made in NTSC or PAL, and they are merely storage devices carrying audio video files compressed inside. If the files are in a resolution of 720×576 pixels, it is termed as PAL DVD, and if the resolution is 720×480 pixels, the DVD is called a NTSC DVD. There are also frame rate differences accordingly, and this is 25fps in case of PAL and 30fps in case of NTSC DVD. This information is taken by the DVD player and it formats this information for display in either PAL or NTSC.
|
In brief: Difference between NTSC and PAL • NTSC stands for National Television Standards Committee, while PAL stands for Phase Alternating Line. • NTSC is used for broadcasting in countries where electricity supply is in 60Hz, whereas PAL is used in countries where electricity supply is 50Hz • PAL has a higher resolution than NTSC • NTSC has higher frames per second speed (30) than PAL (25) • Image quality in PAL is better than in NTSC • A set made in Europe may not work well in the US.
|