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What are the meanings of (and thus the differences between) color temperature, X-color push (example red push), tint, chroma, gamma (are there an alpha and beta?), and color depth, and anything else that describes colors that I didn't list?
 

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This is based on my understanding of them, or at least how they're commonly used, so it's possible it might not be the best description. Or it could be flat out false. I'm sure someone will correct me if I'm wrong.


color temp. - This is usually used to describe what color white is on a display. The values, like 6500K stand for 6500 degrees Kelvin and are used in reference to black body radiation. A black body is a theoretical object which doesn't reflect any light, usually stars are considered black bodies. There's a formula which describes how much light a black body gives off at a certain frequency at a given temperature (color temp.) The higher the temp the "bluer" the light appears. The lower the temp the "redder" the light appears. Which is kind of counter-intuitive since cool is usually associated with blue and warm with red. Since there's a strict formula it allows a number (like 6500) to always mean the same color and makes for a good standard.


color push - Probably just means that a display shows colors pushed more towards a certain color than it should. If a display has a red push then all colors will be too red, and so on.


tint - Like push, if a display has a red tint it means the colors are too red. For NTSC displays the tint control usually controls how the color decoding circuit translates the color signal into the final output color. Usually if you change the tint control in one direction it makes everything more green and more red if changed in the other direction.


chroma - Means color. Video signals (NTSC anyway) are split up into a luminance signal which controls brightness and a chrominance signal which controls color. So the chrominance will control if an object is red or green or yellow, and the luminance will control how bright it is.


gamma - Is another standard way to describe how a signal gets translated to a display output. Specifically it describes how changes in video signal strength (or brightness) get translated to actual output light levels. If something has a linear gamma then doubling the signal input will double the actual light output. If a display has a different gamma, like 2.2 used for PC displays, than doubling the signal value won't necessarily double the light output. The reason for messing with this is to allow a display with limited output range to display a wider range of input signals.


color depth - Is usually used when talking about a digital representation of color. On computer systems for instance colors are represented by three components, red, green, and blue which correspond to the colors of the phosphors on a monitor and the three types of cone cells in our eyes. The color depth is how many bits of data are used to represent each of those component colors. The more bits the more shades of that color you can represent. Most computers use 24 bits per pixel (bpp) which means 8 bits each for red, green, and blue. So you would say it has a color depth of 24bpp.


Sorry, these answers are a bit technical. Let me know if you have any questions and I'll do my best to answer them. I'm certainly not an expert on color and the display of color, but I do work with it on a daily basis. Basically when it comes to using these various controls to set up a display just play with them to see what they do and set them to your liking.
 

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Going off on tangents...


In NTSC, color is encoded using a phase relationship (0 to 360 degrees). Think of a color wheel, red, orange, yellow, green, cyan, blue, magenta, and back to red. I'm not sure which color is represented by zero degrees. Manipulating the tint control corresponds vaguely to turning the color wheel, for example when tilting the reds towards oragne, the yellows will tilt towards greens, the cyans will also tilt towards blues, and so on. Assuming the colors were spaced around the wheel correctly for studio production and also spaced around the wheel correctly for decoding into RGB in the TV set, you can get it right with the tint control. The tint control for NTSC is also called a color phase control.


For component video and digital video, the color wheel part of the video circuitry (the NTSC color decoder) is not used. If a tint control is still operative, it works differently, perhaps faking the above behavior by (most likely) making reds more vivid and cyans less vivid, or making both reds and cyans more vivid, and the same for blue/yellow, which the Pr and Pb of component video stand for.


Push, usually it is red, can be vaguely explained as having the pivot of the color wheel off center. Turning the color wheel won't make all the colors correct at the same time.


Chroma and chrominance are slightly different. One (I forget which) refers to the color after gamma correction has been applied. If you are just talking about color, you can get away with interchanging these two terms.


Chroma Delay -- The color signals (Pb and Pr for component video, or all three, red, green, and blue, of RGB) have to change at the correct time as the electron beam moves across the screen. A common problem is having the Pb and Pr out of sync. relative to the luminance so colors are displaced horizontally such as in a poorly done child's coloring book. Because component video and RGB are carried using three separate cables, differences in the cables can cause chroma delay also.


Video hints:
http://members.aol.com/ajaynejr/vidcolor.htm
 
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