I've been noticing this for years now -- whenever I've watched the LA Lakers, or Minnesota Vikings, or Northwestern Wildcats, or any team that has purple as a team color, their uniforms appear blue on television. I noticed it again on Sunday when I was watching the Vikings/Bears game. I see it again tonight with the Colorado Rockies.
One weird aspect of this is that the graphics the networks use to denote the team's colors definitely appears as purple -- but the uniforms themselves appear as blue.
This doesn't occur in photographs, as pictures in magazines or the newspaper from the very same game yield a purple color for the uniforms. The purple-uniform-as-blue thing happens only on TV.
What is it about the electronics of television that causes this to happen?
This is because CCD cameras that are typically used for television now are sensitive to other wavelengths and can create false colors. One way to see this is to aim a TV remote control (infrared type) at your webcam. You will see a bright bluish white light from it, although it is IR and not visible to the human eye. In the real world, there are unseen sources of IR and also there are dyes in our clothing and everyday items that can fluoresce IR, similar to UV/dayglow colors. Added to the camera's sensitivity for IR, the colors tend to pick up a blue cast.
1) The color sensitivity of the red and blue imaging filters/chips.
2) The wierd man-made dyes used in modern fabric.
There was an extensive discussion of this over on one of the television- related sci. newsgroups several months ago. (Except that it was the weather-girl's purple pant-suit!)
Silver-halide-type film cameras use "negative"/"subtractive" filters (yellow, magenta, cyan), where video (and electronic still cameras) use "positive"/"additive" filters (red, green, blue). One theory is that those "negative" filters have a broader bandpass and don't miss the wierd (aneline dye?) colors in the "plastic" fabric.
Accurate reproduction of color imagery via electronic means is a topic that can fill a book - and has! - but in somewhat simplified terms there are two major problems here:
Both the image source (in this case, the camera) and the display (a CRT) may be "speaking" in terms of RGB values, but may not be using quite the same red, green, and blue (although these ARE supposedly standardized by the broadcast television specifications) or how much of each is supposed to be combined to make "white." This will alter the appearance of the color as displayed vs. what the camera "intended."
No three-primary system can ever cover the entire range of colors perceivable by the human eye (due to the nature and overall shape of the "color space" in which they must be represented). Further, none of the three primaries used - either by the camera or in the CRT - is fully saturated, which additionally restricts the range of colors which can actually be reproduced correctly. Truly saturated purples and yellows are difficult if not impossible to produce in the typical RGB system.
In addition, the color encoding system used in television ("NTSC" encoding) imposes additional limits, and also some unique problems in obtaining accurate and repeatable colors. The reasons are a bit much to go into in a short posting, but again really accurate purples wind up being difficult to convey properly. You CAN get a reasonably good purple out of the system - as evidenced by what you're seeing in the network-generated graphics - but keep in mind that THOSE are artificially created by a system that can be biased in favor of greater saturation of these colors, rather than a good balance and accuracy overall.
If you'll forgive the plug, I cover this in reasonable detail in my book "Display Interfaces," which has sections both on color in general and on the system used to encode color for broadcast television. (It's part of the SID-Wiley series on display technology, published by John Wiley & Sons.)
Something like 8% of the male population - this condition is linked to a missing gene on the X chromosome, so for it to affect a female it has to be missing on both Xs. However, this results in the inability (or reduced ability) to distinguish red and green; it would not account for differences in perceived color between a television image and the real world.
You could be correct. However, there is a psychological compensation factor that blurs this issue. Those with this deficiency can, in certain environments, fill in the missing data by using brightness and contrast and context. It's not as simple as most think.
Actually, there are two "red-green" forms of colorblindness, both of which very disproportionately affect males.
One is deuteranopia, where reds and greens look alike in hue but without red objects looking darker than they should. The other is protanopia, which is sometimes known as "red blindness" because it makes red objects look darker than they should in addition to making reds and greens similar or somewhat similar in hue.
Including the mild/partial forms known as protanomaly and deuteranomaly. The severe forms (protanopia and deuteranopia) affect more like 1% of the male population.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.