Quote:
Originally Posted by TheBundo
Go look up real close at a tube style color TV. Only 3 colors, I think, RGB ?
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THis is not what is being discussed when we say 65536 colors. Most (all?) color displays are RGB at heart. Each pixel is created from a red,green and blue subpixel. In early systems, like CGA,the monitor had a digital input. What that means is that each color could be either on or off. That makes a total of 16 different combinations,or 16 colors.
More modern vga type CRT monitors have analog inputs and can display an infinite number of colors per channel. The video display hardware however is digital in nature and deterimines the number of colors. If there are 8 bits per color,thats 256 colors per channel or a total of over 16 million colors. Many adapters support 32bit color in several variants,such as 10bits per pixel with 2bit transparency,or 8bits per channel with 8bit transparency.
Modern monitors however are mostly LCD displays. These displays are digital by nature. The display itself will be able to handle a particular bit depth. Some displays will handle 8bits per pixel (24bit color) others will handle only about 65k colors. In many cases you wont notice the difference. Ive seen LCD projection TVs that look very good under most circumstances yet only display 65536 colors. With monitors and TVs analog video,or higher bit depth digital video (DVI or HDMI) are converted down to whatever the LCD can display.
64 thousand or 24 million colors sounds pretty good so you might wonder why alot of scanners have 10 or 12bits or more per pixel of color resolution (as well as many professional video and image formats) The reason is that under some circumstances you will notice the difference. In a normal photograph or tv show you might not notice. However if you make a gradient on screen,from light green to dark green,you will notice some banding. In fact,on the cheaper TVs with lower color resolution displays you see this in certain places if you know what to look for. Look for dark scenes with alot of lense flare effects. In these scenes you will see color banding around the lights. In 24bit color its not as apperant,but under some circumstances it can be seen. (but you really have to look)
On a pocket PC you might ask whats the point of being able to display any of 24 million colors when the display only has about 300,000 pixels. The problem is not displaying 24 million colors but displaying for instance 256 levels of red to make the shadows on a rose petal look good. While it woul d be nice to have a 24 bit display,the display on the pocket PCs is fine. I rarely notice any of these issues,and even if I do its really not that bad.