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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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TV Pictu What Does "Calibration" Mean???
TV Pictu What Does "Calibration" Mean??? Calibration. To calibrate. With regards to TV sets - of any type - I suspect two things have stood in the way of this process: #1. Most set owners and folks in general, outside of the scientific community, don't know what the dang word even means! And #2. Modern digital TVs are so "good" most people think they don't even need calibration. Succinctly, calibration means to align something to a given standard, or set of standards. These standards may be physical, electrical, chemical, or in the case of image reproduction, a certain range of color and brightness when standardized patterns are displayed on a TV. ========== The way I have recently started to explain what I do to TVs to the average person is to draw a basic shape on a piece of paper, I.E. a triangle. To the right of that I draw an arrow, then a rectangular box, another arrow, and a blank space. I then show this to the person, explaining that the triangle is the subject on TV, and the box is their TV set. I then ask them what should they see to the right of all that, after it comes out of their TV set. They answer, "a triangle"? So I draw a circle! (or, a distorted triangle) The person looks at me, "what?" I tell them, without calibration, this is what your TV does to the image of subjects transmitted to it, via inaccurate color, off tint, or too bright or incorrect contrast. Your TV may wow you out of the box, but that factory setting was intended to SELL IT to you, not for long-term TV or movie viewing, or game playing. Plus, it may shorten the set's life. I then explain the two types of calibration: Basic(brightness, contrast, sharpness, color, tint - the basic user controls), and, advanced(Basic, plus internal color temperature and grayscale alignment.). I then explain that most reputable brands of TVs today(Sony, JVC, Samsung, Pioneer) will deliver an accurate picture with just the basic controls properly set. Cheapo brands(Daewoo, Insignia), or older CRT(tube) TVs might need more advanced additional adjustments to get them in line. If they ask me what all this will do, I tell them: You will see, if not exactly, an image much closer to what the producer or tv control room engineers see when they make a TV show or a movie. Plus, the image will be far less stressful to the eye, and you might even save energy! ========== This usually sells them, instead of just asking them, would you like your TV "calibrated"? Calibration is a big, nerdy, multi-syllable word that few understand, and perhaps shouldn't even be used to describe the process of aligning a display and making it transparent to whatever is shown on it. No WONDER "display calibration" or "tv calibration" has fallen out of favor! Waiting for the crickets .... - Switch accounts - Desktop |
#2
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TV Pictu What Does "Calibration" Mean???
Well that's all fine and good, but why did you use the form of a question in the title ?
Anyway, there is a disk out there called "Video Essentials" which is supposedly a great aid in doing that. However, for an accurate greyscale you need something to which to compare. For video cameras they had what were called lightboxes which supposedly had a specific color temperature. With a monitor, maybe you can compare to a high brightness piece of paper lit by a lamp with a specific color temperature. Or perhaps sunlight. Though things can run off still, it is nowhere near as bad as CRTs were. If they weren't burned in enough after cathode activation they would drift, and later those miniature cathodes got hotter with increased beam current and drifted, necessitating AKB. (Auto Kine Balance) And then there is convergence and purity. The Earth's magnetic field affected the purity quite a bit, and convergence to a lesser degree, except on projection TVs. The LCD TVs do not really have these problems, they are going to inherently be more accurate out of the box. Same with plasmas but the phosphors in a plasma can weaken with age like any other phosphor. Someone told me the gas in them wears out, and that reduces color temperature. I do not believe it, that should affect all colors equally. I think the blue phosphor wears out first. Blue phosphors are the least efficient and therefore will get more drive. While there are no cathodes, the phosphor does still burn in and weaken with heavy use. There is no convergence or purity adjustment on plasma or LCD (which includes what they call LED now). Greyscale and color demodulation, are all there is, and with other than NTSC (composite or SVHS) there is no color demodulation either. |
#3
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TV Pictu What Does "Calibration" Mean???
wrote: "Well that's all fine and good, but why did you use the form of a question in the title?"
Because it seems in the last 10 years calibration, or at least the very concept of it, is becoming marginalized, less relevant. The occurrence of the word "calibration" has dropped significantly since the early 2000s according to searches I conducted in usenet groups related to video technology and production. I sincerely want to share my calibration experiences with others because I'm so excited by what it has done for my TV and video viewing experience. My problem is adjusting my "elevator speech" so that the common man(woman) 'get' what calibration does for their equipment and their viewing. |
#4
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TV Pictu What Does "Calibration" Mean???
I've worked in broadcast and post production since 1976 and calibrated many monitors, some used for THX film transfers and verified by their tech. Calibration was mandatory with CRT monitors and on a regular basis. The new TVs are amazingly consistent and I find no desire and certainly no need to 'tweak' them. In fact, unless you're very qualified I would not allow you to touch my TV. G² |
#5
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TV Pictu What Does "Calibration" Mean???
wrote: "
The new TVs are amazingly consistent and I find no desire and certainly no need to 'tweak' them. In fact, unless you're very qualified I would not allow you to touch my TV. G² " So if I understand you correctly, If you were to buy a brand new flat panel set, connect it all up and start watching it, you would leave the user menu settings all in their factory positions? |
#6
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TV Pictu What Does "Calibration" Mean???
On Wednesday, October 21, 2015 at 8:13:42 AM UTC-4, wrote:
TV Pictu What Does "Calibration" Mean??? Calibration. To calibrate. With regards to TV sets - of any type - I suspect two things have stood in the way of this process: #1. Most set owners and folks in general, outside of the scientific community, don't know what the dang word even means! And #2. Modern digital TVs are so "good" most people think they don't even need calibration. Succinctly, calibration means to align something to a given standard, or set of standards. These standards may be physical, electrical, chemical, or in the case of image reproduction, a certain range of color and brightness when standardized patterns are displayed on a TV. ========== The way I have recently started to explain what I do to TVs to the average person is to draw a basic shape on a piece of paper, I.E. a triangle. To the right of that I draw an arrow, then a rectangular box, another arrow, and a blank space. I then show this to the person, explaining that the triangle is the subject on TV, and the box is their TV set. I then ask them what should they see to the right of all that, after it comes out of their TV set. They answer, "a triangle"? So I draw a circle! (or, a distorted triangle) The person looks at me, "what?" I tell them, without calibration, this is what your TV does to the image of subjects transmitted to it, via inaccurate color, off tint, or too bright or incorrect contrast. Your TV may wow you out of the box, but that factory setting was intended to SELL IT to you, not for long-term TV or movie viewing, or game playing. Plus, it may shorten the set's life. I then explain the two types of calibration: Basic(brightness, contrast, sharpness, color, tint - the basic user controls), and, advanced(Basic, plus internal color temperature and grayscale alignment.). I then explain that most reputable brands of TVs today(Sony, JVC, Samsung, Pioneer) will deliver an accurate picture with just the basic controls properly set. Cheapo brands(Daewoo, Insignia), or older CRT(tube) TVs might need more advanced additional adjustments to get them in line. If they ask me what all this will do, I tell them: You will see, if not exactly, an image much closer to what the producer or tv control room engineers see when they make a TV show or a movie. Plus, the image will be far less stressful to the eye, and you might even save energy! ========== This usually sells them, instead of just asking them, would you like your TV "calibrated"? Calibration is a big, nerdy, multi-syllable word that few understand, and perhaps shouldn't even be used to describe the process of aligning a display and making it transparent to whatever is shown on it. No WONDER "display calibration" or "tv calibration" has fallen out of favor! Waiting for the crickets .... - Switch accounts - Desktop That would depend. We have a Panasonic Plasma TV - the factory settings are *very* bright and the color mix verges on the cartoonish. "Calibrating" in that case allows the user to set the color range, average brightness and similar parameters to a more reasonable setting. One can purchase a 'kit' to help with this, and/or use other means to get the colors true. Once done, as otherwise noted, the system seems to remain remarkably stable, even through power-failures. That would be my take on the use of that term-of-art for our particular unit. Peter Wieck Melrose Park, PA |
#7
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TV Pictu What Does "Calibration" Mean???
wrote: "- show quoted text -
- Switch accounts - Desktop That would depend. We have a Panasonic Plasma TV - the factory settings are *very* bright and the color mix verges on the cartoonish. " So you have observed, and agree, that factory default settings on consumer TVs such as your Panasonic and on my Samsung LED are not ideal for extended viewing. "Calibrating" in that case allows the user to set the color range, average brightness and similar parameters to a more reasonable setting. One can purchase a 'kit' to help with this, and/or use other means to get the colors true. Once done, as otherwise noted, the system seems to remain remarkably stable, even through power-failures. " And you agree with calibration in your particular case. I did notice that you seem to think that calibration is some- thing that must be done periodically(every year or two for example). That may have applied in the case of CRT-based TVs or projectors, yes. But not with modern digital flat technology - UNLESS - you change one of your input sources, or upgrade, I.E. from a standard DVD to a Blu-Ray deck. You then recalibrate that input for that device. I tell all of my customers this: that their calibrated settings should not drift for at least a decade. "That would be my take on the use of that term-of-art for our particular unit. " Peter Wieck Melrose Park, PA " Not sure what you mean by "term of art". Please elaborate. |
#8
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TV Pictu What Does "Calibration" Mean???
On Thursday, October 22, 2015 at 9:29:41 AM UTC-4, wrote:
And you agree with calibration in your particular case. I did notice that you seem to think that calibration is some- thing that must be done periodically(every year or two for example). No, I stated that the settings, once done, were remarkably stable, even through power-failures. I did have to re-calibrate after a 6-day failure (Hurricane Sandy), but not for failures as long as several hours. That may have applied in the case of CRT-based TVs or projectors, yes. But not with modern digital flat technology - UNLESS - you change one of your input sources, or upgrade, I.E. from a standard DVD to a Blu-Ray deck. You then recalibrate that input for that device. I tell all of my customers this: that their calibrated settings should not drift for at least a decade. I have not experienced that need - we switched about 2 years ago from a basic DVD player to a compatible, self-upgrading blue-ray DVD with no visible need to re-calibrate - and the software with the kit verified this. "That would be my take on the use of that term-of-art for our particular unit. " Not sure what you mean by "term of art". Please elaborate. Term-of-Art: A word, combination of words or phrase specific to one thing that is used outside of its common definition. To me the term "calibrate" is specific to measuring devices, meters, tube testers, signal generators, rotameters, gauges and so forth that are set to a specific standard such that measurements from them can be trusted. I would not generally consider arbitrary settings based, in part, on taste rather than independent standards, would be any sort of 'calibration'. At least, again, as I understand and would normally use the term. There are those that prefer bright settings and cartoonish colors. De gustibus et coloribus non est disputandum. Quidquid latine dictum sit, altum videtur. Peter Wieck Melrose Park, PA |
#9
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TV Pictu What Does "Calibration" Mean???
"me the term "calibrate" is specific to measuring devices, meters, tube testers, signal generators, rotameters, gauges and so forth that are set to a specific standard."
Likewise! DVD test patterns also count, as long as one follows instructions on what to look for when the specific control(brightness, contrast) is adjusted optimally. I still sense a lot of skepticism in your responses regarding display ALIGNMENT - there, I just found a new name for it that makes sense! |
#10
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TV Pictu What Does "Calibration" Mean???
On Wednesday, October 21, 2015 at 9:37:13 PM UTC-7, wrote:
I've worked in broadcast and post production since 1976 and calibrated many monitors, some used for THX film transfers and verified by their tech. Calibration was mandatory with CRT monitors and on a regular basis. The new TVs are amazingly consistent and I find no desire and certainly no need to 'tweak' them. In fact, unless you're very qualified I would not allow you to touch my TV. Generally, there's no calibration in an LCD TV that requires touching. Digital signal, not affected by movable magnets or variable resistors. If you use your TV for a computer monitor, though, and have a color printer: you ought to calibrate the video card or the printer driver so that the color prints produce the same colors as the screen display. Getting the correspondence right is important for artistic uses, and requires (1) controlling reflected light off the screen (2) getting as much color gamut and contrast on the screen as on the paper (not easy, might require special paper) (3) controlling the illumination light when viewing printed material (4) adjusting R, G, B zero points (5) adjusting R, G, B brightnesses (6) adjusting for any nonlinearity (usually called 'gamma correction') for R, G, B (7) readjusting from time to time, as papers, inks, phosphors may age. It can be hard to find and rectify any adjustments. Or, it can be easy - Apple made a ColorSync monitor with internal light sensors that did recalibration in a few seconds if you pressed the front-panel button). |
#11
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TV Pictu What Does "Calibration" Mean???
On Thursday, October 22, 2015 at 2:58:02 PM UTC-4, wrote:
"me the term "calibrate" is specific to measuring devices, meters, tube testers, signal generators, rotameters, gauges and so forth that are set to a specific standard." Likewise! DVD test patterns also count, as long as one follows instructions on what to look for when the specific control(brightness, contrast) is adjusted optimally. I still sense a lot of skepticism in your responses regarding display ALIGNMENT - there, I just found a new name for it that makes sense! Mpffff..... Here we go again.... Alignment: My primary hobby is vintage radio restoration and repair, so "alignment" is a very specific term. Shifting that term from rF to Visual alignment is not a stretch, just not what leaped to mind when I read your assignment of this term to that process. Telescope people call it "collimation", musicians call it "tuning" but they are all forms of aligning some sort of information for greater accuracy/clarity. Peter Wieck Melrose Park, PA |
#12
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TV Pictu What Does "Calibration" Mean???
On Thursday, October 22, 2015 at 1:24:35 AM UTC-7, wrote:
So if I understand you correctly, If you were to buy a brand new flat panel set, connect it all up and start watching it, you would leave the user menu settings all in their factory positions? No. That looked bad because it was in 'store demo' mode. I don't consider the 'user adjustments' namely brightness, contrast, saturation (color), back light and sharpness to fall into the 'calibration' category. Calibration to me involves individual RGB gain, lift and gamma. These were finicky with CRTs but don't need much if any tweaking with LED lit LCD sets. G² |
#13
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TV Pictu What Does "Calibration" Mean???
whit3rd wrote: "Generally, there's no calibration in an LCD TV that requires touching.
Digital signal, not affected by movable magnets or variable resistors. " So I will ask you the same question: If you bought and unboxed a brand new flat panel TV for your home, would you leave the user and semi-advanced settings in their factory mode? Have you actually seen a TV(any TV, CRT, Plasma, LED, etc) in its factory defaults? Again, I'm talking about the SETTINGS, not the broadcast or cable signal fed into the back of it. And no, for the purposes of this dis- cussion, there is no concern of "drift" because we are in the micro- circuit digital realm. |
#14
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TV Pictu What Does "Calibration" Mean???
Your silence on this subject speaks
volumes. Out of the box, a new con- sumer grade TV is like staring at the midday sun for a half-hour to an hour. It is typically set to "Vivid" or "Dynamic" mode, which is useful only for display in a retail sales floor environment. Contrast, color and sharpness are cranked, color temperature is skewed to 10,000+Kelvin - ultra blue, and every so-called "enhancer" under advanced settings is checked(skin tone enhancer, black level enhancer, digital noise re- duction, etc.) Backlight(if it's a LED or LCD) is all the way up, etc. Just taking it out of Vivid, and turning off all that CRAP in the advance menu gets you from some vague location in the South Bronx INTO Yankee Stadium, in terms of accuracy! The professional calibration we discussed here will take you from a seat somewhere in the right- field upper deck right onto home plate. And there are no "personal preferences" when it comes to picture settings - only one right combination of basic and advanced controls, and 1,000 possible WRONG combinations. it's your choice: Stare at the sun every night during the 6 o'clock news, or see what the host and the world through the cameras really looks like. |
#15
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TV Pictu What Does "Calibration" Mean???
In article ,
whit3rd wrote: On Wednesday, October 21, 2015 at 9:37:13 PM UTC-7, wrote: I've worked in broadcast and post production since 1976 and calibrated many monitors, some used for THX film transfers and verified by their tech. Calibration was mandatory with CRT monitors and on a regular basis. The new TVs are amazingly consistent and I find no desire and certainly no need to 'tweak' them. In fact, unless you're very qualified I would not allow you to touch my TV. Generally, there's no calibration in an LCD TV that requires touching. Digital signal, not affected by movable magnets or variable resistors. If you use your TV for a computer monitor, though, and have a color printer: you ought to calibrate the video card or the printer driver so that the color prints produce the same colors as the screen display. Getting the correspondence right is important for artistic uses, and requires (1) controlling reflected light off the screen (2) getting as much color gamut and contrast on the screen as on the paper (not easy, might require special paper) I'm pretty sure it's the other way around -- any decent screen will have a much broader gamut than any subtractive color process (i.e. any sort of image printed on paper). Same with contrast ratio -- the screen wins by an order of magnitude or better. Isaac |
#16
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TV Pictu What Does "Calibration" Mean???
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#17
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TV Pictu What Does "Calibration" Mean???
Cyndrome Leader wrote: wrote:
Your silence on this subject speaks volumes. Out of the box, a new con- sumer grade TV is like staring at the midday sun for a half-hour to an hour. It is typically set to "Vivid" or "Dynamic" mode, which is useful only for display in a retail sales floor environment. Contrast, color and sharpness are cranked, color temperature is skewed to 10,000+Kelvin - ultra blue, and every so-called "enhancer" under advanced settings is checked(skin tone enhancer, black level enhancer, digital noise re- duction, etc.) Backlight(if it's a LED or LCD) is all the way up, etc. The problem I see with most LCDs is the color temp due to the LED backlighting. Everything is way too cold (blue). Except for that, just peek in a bar with multiple TVs, they're not perfectly matched, but far closer than in the days of CRTs or plasma stuff. There's no phosphors or electron guns to weaken at different rates. The drift (in everything) in the plasma airport arrival/departure screens was pretty amazing too, even if you cut some slack for those displays having been used in the worst possible conditions. " Cyndrome: The reason you are seeing those "way too cold" color temperatures is because in the advance settings the highest/bluest color temperature is set by default! As for the creature cantina scene - of course the TVs in there are not matched: different mfgs have different factory default settings; but what those settings do have in common is: they were selected to make their product stand out on a sales floor - NOT to be watched for any appreciable length of time. Bet you a five-legged horse that if even just the user controls(color temp set to neutral instead of high, backlight on LEDs set in half, and the bright, contrast, color, sharpness all set via test DVD) you'd be hard pressed to see any difference between sets at opposite ends of the bar - assuming they are all tuned to the same game, as they likely all will next week for the series. What more can I do to convince you guys that OOB (out of the box) settings are no good for a consumer display, or for your eyes? In fact, I find the factory "BUY ME, BUY ME!" settings on modern flat panel TVs are worse than the factory defaults on any old CRT tube I've EVER seen. |
#18
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TV Pictu What Does "Calibration" Mean???
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#19
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TV Pictu What Does "Calibration" Mean???
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#20
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TV Pictu What Does "Calibration" Mean???
Cyndrome wrote: "How do you suggest adjusting a projection system? "
A Blu-Ray Digital Video Essentials disc *should* produce the same results for your projector as it would for any flat panel HDTV. Just follow all instructions. |
#21
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TV Pictu What Does "Calibration" Mean???
"The problem I see with most LCDs is the color temp due to the LED
backlighting. Everything is way too cold (blue). Except for that, just peek in a bar with multiple TVs, they're not perfectly matched, but far closer than in the days of CRTs or plasma stuff. There's no phosphors or electron guns to weaken at different rates." Most of them now have user color temperature adjustments. That will be at the highest setting when it leaves the factory. The LEDS are chosen for the high blue output because to use the display to lower the color temperature is much cheaper than to raise it. In terms of brightness. And it does not react as well as CRTs did. But in both, if you DO want higher color temperature you need to boost the blue. Reducing the red and green is not the right way to do it. |
#22
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TV Pictu What Does "Calibration" Mean???
wrote: "Most of them now have user color temperature adjustments. That will
be at the highest setting when it leaves the factory. ^Correck!^ Folks I have come to the conclusion that the majority of people don't even know these new-fangled panels HAVE settings or a menu under which settings can be found. I'm dead serious. And they live with their TVs looking like cartoons not knowing that they are getting only 5% of out of their investment's potential. A damned SHAME, as is their attitude when I offer to make it better: "It's fine the way it is" "It's brand new; that's the way it's supposed to look." "LEAVE IT ALONE".... And that's the toughest part of being a calibrator - or at least, someone who knows better. |
#23
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TV Pictu What Does "Calibration" Mean???
Somewhat like the people who leave their stereo at flat response. the bass and treble controls are there to be used. Every recording is not perfect and every speaker is not perfect, especially in a real room.
How the shoot these new movies and shows annoys me. Color effects, the blacks are green or whatever. And I know it is them because if you turn the color all the way down you have a good greyscale. Camera angles shifting like a damn toddler had the camera. And geometry ? Either it is letterboxed, cropped on the sides or overscanning because they haven't gotten their aspect ration **** together. |
#24
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TV Pictu What Does "Calibration" Mean???
On Saturday, October 24, 2015 at 12:54:22 PM UTC-4, wrote:
Somewhat like the people who leave their stereo at flat response. the bass and treble controls are there to be used. Every recording is not perfect and every speaker is not perfect, especially in a real room. How the shoot these new movies and shows annoys me. Color effects, the blacks are green or whatever. And I know it is them because if you turn the color all the way down you have a good greyscale. Camera angles shifting like a damn toddler had the camera. And geometry ? Either it is letterboxed, cropped on the sides or overscanning because they haven't gotten their aspect ration **** together. ___ Actually jurb, the default TV settings are like having the bass & treble jacked fully clockwise, or the graphic equalizers set like smileys - middle sliders down, and sliders toward the ends higher and higher. As far as aspect ratio is concerned, 16:9 or "screen fit" will accommodate most viewing scenarios. I'm really annoyed by those who insist on stretching 4:3(old fashioned TV) pictures to fit their wide-screen HD theater, so J.J. from "Good Times" looks wider than superintendent Bookman. LOL! |
#25
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TV Pictu What Does "Calibration" Mean???
For those that don't think calibration - or at least
proper adjustment of the basic six controls - is important: http://www.avdomotics.com/listmanage...calibrated.jpg |
#26
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TV Pictu What Does "Calibration" Mean???
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#27
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TV Pictu What Does "Calibration" Mean???
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#28
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TV Pictu What Does "Calibration" Mean???
Cyndrome Leader wrote:
"yes, and there are different types of phosphor. Some look better than others where color temp matters. " And there are adjustments available on most panels to being all of those into grayscale spec. |
#29
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TV Pictu What Does "Calibration" Mean???
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#30
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TV Pictu What Does "Calibration" Mean???
On Monday, October 26, 2015 at 6:05:40 PM UTC-4, Cydrome Leader wrote:
com wrote: Cyndrome Leader wrote: "yes, and there are different types of phosphor. Some look better than others where color temp matters. " And there are adjustments available on most panels to being all of those into grayscale spec. Adjustable backlight color temp on cheapo televisions? Not the backlight - the overall picture. I've seen color corrected LED backlights on high end computer displays. I use a 4k Eizo that has this feature, it's not tunable but the color temp has a few settings and only the highest one is harsh blue, as it should be (and also not used as it looks bad, like televisions at the store). "harsh blue, as it should be" ??? Are you serious? |
#31
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TV Pictu What Does "Calibration" Mean???
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#32
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TV Pictu What Does "Calibration" Mean???
Cydrome Leader wrote: wrote:
"exactly. If you try to compensate for a horrible backlight you're going to lose the full gamut the display should have been able to show. " And this is where colorimeter-based calibration comes in. By adjusting the bias/gain, and the RGBs, you can compensate for any backlight flaws and maintain correct color gamut. "Serious. 10k color temp looks bad on a good monitor, and that temp is even far exceeded by cheap displays. " So given that, and your first quoted statement above, would you still keep the OOB settings on a consumer display, or would you at least attempt to get the basic settings closer to standardized positions? |
#33
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TV Pictu What Does "Calibration" Mean???
On Saturday, October 24, 2015 at 6:58:18 AM UTC-4, wrote:
Folks I have come to the conclusion that the majority of people don't even know these new-fangled panels HAVE settings or a menu under which settings can be found. I'm dead serious. And they live with their TVs looking like cartoons not knowing that they are getting only 5% of out of their investment's potential. We bought our first flat screen this year when a CRT finally died. (still have 3 more in the garage, can't get rid of them) I did not know there were settings until I read this thread. I do recall the colors didn't look quite right at first, but ....sigh......we got used to them. So you're making a good case for some adjustments. Is this stuff in the owner's manual? |
#34
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TV Pictu What Does "Calibration" Mean???
On Saturday, October 24, 2015 at 12:54:22 PM UTC-4, wrote:
Somewhat like the people who leave their stereo at flat response. the bass and treble controls are there to be used. Every recording is not perfect and every speaker is not perfect, especially in a real room. Well - this is a horse of an entirely different color. First, a confession: Due to this being one of the facets of my hobby, I have no less than seven (7) functioning, dedicated audio systems in play. Four are in my "radio room" one in the living room, and the most serious one in the library. The seventh is at our summer house, and is primarily a weekend warrior. Speakers range from AR3a to Magnepan MG-IIIa, and include both Revox and AR sub-sat systems as well as vintage AR M5s. So, the vice has been well-established. The house is a center-hall colonial with 10' ceilings, plaster walls, hardwood floors and lots of wood trim. Room sizes vary from 17' x 24' x 10' (library) to 12' x 15' x 9' (radio room). a) I have found that with some care and a very understanding wife, speakers may be placed in about any room without needing equalization. b) Getting a good soundstage - which is emphatically NOT a single point - is a little more difficult, but not impossible - and why I favor placing speakers on the long wall of a room, not the short wall. c) There are times when I will use the bass/treble/midrange controls on my pre-amps - but that will be specific to a recording, not a general setting. I do also own an equalizer - but in the last 10 years, it has seen use only to the extent that I make sure it is working properly. And I also own a Citation 17 with equalization built-in, nice but not much used. d) I find that adequate power such that one may achieve substantial volume without the threat of clipping is far more useful to good sound than any sort of 'shaping' applied to the signal. I have a (very) few recordings with a peak-to-average of very nearly 30dB, such that 'enough power' is not an idle expectation. Things that are 'there to be used' are often not of much use if any thought is applied. https://c1.staticflickr.com/1/46/156...1ea5a376db.jpg Peter Wieck Melrose Park, PA |
#35
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TV Pictu What Does "Calibration" Mean???
"And this is where colorimeter-based calibration comes
in. By adjusting the bias/gain, and the RGBs, you can compensate for any backlight flaws and maintain correct color gamut. " No. here is a reason there were no LED LCD TVs in the past. They could not get the color right because the wavelengths they needed were simply not there. So they built those HV supplies and used those CCFLs with their own special phosphor. Well it isn't all that special. The LCD panel has to separate the colors, and there are only so many efficient ways of doing that. You have to have the colors it needs. The spectral output has to be right and matched to not only the panel, but the circuitry.. The days of the 90 degree color demodulation angle being the last word are over. Red is not really red, green is not really green and blue is not really blue. At least as defined by the old standard. They can do whatever they want now, and DLPs took to using seven colors. Like having a seven gun CRT. Try just demodulating I and Q now. (the original red and blue signals, kinda) One thing though, if you DO deem it that important, what is your reference ? A piece of paper ? Lit by what ? The way I see it you would need a lightbox such as used for color camera calibration. If you do not have that, how do you know what is white ? |
#36
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TV Pictu What Does "Calibration" Mean???
"Well - this is a horse of an entirely different color. "
You an AKer ? Anyway, in response, speakers run 5, 6, 7 dB off, microphones about the same. Amps, tuners, whatever, consider them good within 3 dB. And people are afraid to use tone controls ? Where is that in the Bible ? Where is that in the Constitution ? What's more, when turned all the way up that bass control is doing what it is supposed to do. Or all the way down. It was endowed by its creator with that ability. It is your free will to use it or abuse it. Like a gun, well at least as far as some woofers are concerned but they are just paranoid... Bose had no shame in using a permanent EQ. Neither did I. Years ago I had speakers used to have a small woofer and like an 8 or 10 inch passive radiator which I replaced with a four ohm woofer. It was not good, but using the full range off a Soundcraftsmen ten band EQ I got them to sound good. And when I played a few other things on them I started liking them better and better. Damn that bass was smooth. The settings were 31 Hz at +max, 62 at 0, 125 Hz at -max (min) and the rest gradually up to the center from there to about the sixth band. It sounded fantastic, but was inefficient as hell. First of all it was 2.3 ohms, poison to at least half of the amps known in existence, or not actually... The lights dimmed when I cranked these babies up. Eventually they became the rear channels in my quad system. Fed them with a supposedly low power Sansui 771. I scoped it once and don;t remember the reading but it was well over a hundred a channel into that 2.3 ohms. The front was the Marantz 4270 running into speakers I put together. A 12 inch three way system, decent dome tweeters, noting fancy ad did not sound perfect, but I had an EQ for them as well. Separate EQs for front and back. Yup. Once set, I believe the sound was damn hard to beat. Nobody did back then, at least in the current crowd. And I had it with the Advent five foot silver screen job with the mirror out front, AND MINE WAS CALIBRATED. Someone has just changed all three CRTs but it had another problem nobody could fix. Nobody else that is. You look at these things and the picture is trapezoidal, the convergence is ****, you can't read the letters sometimes because it is so bad. Not mine. Mine was perfect. Convergence within a raster line width everywhere on the screen. I figured out a little design defect that was keeping the others from having that. It was radiation from one wire to another, polluting one of the waveforms going to the convergence waveform board. It caused an error at the right side and most people just made it overscan, not me. On a five foot diagonal screen my overscan was less than an inch on each side. Now remember how long ago this was. Your TV picture got smaller when your fridge started not long before that. I wouldn't mind having one of those old sets now. Not that I have anywhere to put it, but if I did... |
#37
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TV Pictu What Does "Calibration" Mean???
wrote: "One thing though, if you DO deem it that important, what is your reference ? A piece of paper ? Lit by what ? The way I see it you would need a lightbox such as used for color camera calibration. If you do not have that, how do you know what is white ? "
This will be my last reply to you, since it seems your mind is clearly closed to TV calibration: My ref. source is one of several good test pattern DVDs out the HD Digital Video Essentials on Blu-Ray, Spears & Munsil, etc. There are also pattern generators out there, from Quantum and Spectra Cal. You put up the patterns, stick a sensor on your screen, and adjust what the laptop software tells you to. And now you are on your own. I'm going to respond to someone who at least seems curious about this subject. |
#38
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TV Pictu What Does "Calibration" Mean???
Tim R. wrote: "So you're making a good case for some
adjustments. Is this stuff in the owner's manual? " Welcome to the newsgroup! The owners manual mainly explains how to access the settings and (sort of) what each control does. I can get you started, but first I need to know what type of flat panel you have: LCD/LED(both are backlit) or Plasma. For the backlight types, the first things you want to do is (1) turn the backlight down from full, to about halfway, and (2) under advanced settings, turn off any "eye candy" - garbage like skin tone enhancer, black level enhancer, edge enhancer, and digital noise reduction. Next, get the TV out of "Vivid" picture mode. All that is designed to do is shorten the life of your TV so you can go out and buy a new one in 3-4 years(!). Start with those things and tell me what you see. It will not be as bright as you were used with those showroom settings, but it's not supposed to be. |
#39
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TV Pictu What Does "Calibration" Mean???
On Thursday, October 29, 2015 at 6:14:25 AM UTC-4, wrote:
For the backlight types, the first things you want to do is (1) turn the backlight down from full, to about halfway, and (2) under advanced settings, turn off any "eye candy" - garbage like skin tone enhancer, black level enhancer, edge enhancer, and digital noise reduction. Next, get the TV out of "Vivid" picture mode. All that is designed to do is shorten the life of your TV so you can go out and buy a new one in 3-4 years(!). I did that (except I realize I left noise reduction on) and I get a kind of washed out appearance, like water colors instead of oils. I left it that way to see if I'd get used to it. My wife and daughter have not commented - really they watch the majority of TV. But I didn't tell them what I did, I'll wait a day and ask. What made the most difference was removing Vivid. |
#40
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TV Pictu What Does "Calibration" Mean???
Tim R:
OK. Next I need you to select picture mode "Standard" or "Custom". I need to know the scale and present setting of each of the following: Backlight Contrast Brightness Color Tint/Hue Sharpness. I.E. "Contrast: 0..........50.......100, presently 90. etc. Before you do that, check color temperature setting. Move it to Neutral, or Warm1, if available. |
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