EDTV vs. HDTV
| ED and HD in brief. When looking at purchasing a new plasma TV you will be faced with number of choices, including EDTV (enhanced definition) or HDTV (high definition), so what is the difference? The simple answer is the HDTV has a higher "native" resolution than the EDTV version. The number of horizontal lines projecting the picture differs, EDTV has at least 720 lines, and HDTV has 1080. The picture quality on both is astounding; particularly when compared to conventional television picture quality. The bottom line is the increased resolution of the HDTV display will give you approximately a 20% improvement in viewing quality, and the difference in picture quality will be reflected in the price you pay, which can be as much as 30% on like-for-like models. Interlacing and progressive signals. You will come across the terms "interlacing" and "progressive scanning"; the terms refer to the way a picture is sent to the screen. Let's assume a picture is being viewed on a wide screen with 720 horizontal lines. The signal received by a television feeds the picture from top to bottom along the horizontal lines, each frame taking 1/60 of a second to appear, as each frame is projected continuous motion is seen by the viewer. Interlacing refers to a particular way the signal is drawn by the screen. This signal is sent to the screen in two passes; the first is sent to the lines with odd numbers and the second sent to lines with even numbers, each pass taking 1/30 of a second. |
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