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November 9th, 2004, 06:14 PM | #1 |
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Finally got a REAL production monitor- a few questions.....
Finally took the leap and picked up a true professional production monitor. The Sony PVM-14L5. Very nice unit- seems to be much high res than my little Panasonic 14" television I was using before this. I can see every imperfection in my video now! lol
Anyway I have a question about color temp. I understand the process of calibrating the monitor using NTSC/SMPT color bars but am unsure as to what clor temp to choose. There is "D65" and "D93". I'm assuming this means 6500k and 9300k. To my eye the 65's look a bit too orangy. Does it matter which you choose? Is there one that is considered more "accurate"?! I know the principal of color temp with CRT monitors...and you'd want to go warmer (lower K) if your doing print. How does this translate into the world of production monitors? |
November 9th, 2004, 06:55 PM | #2 |
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D65 will give you the correct gray scale etc. for NTSC video. D93 will give the wrong highlights.
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November 9th, 2004, 07:01 PM | #3 |
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What do you mean? The only way to get accurate color is go D65? How does D93 give "wrong highlights"?
Oh yeah...I also forgot to ask- isn't "Blue Only" supposed to be blue? My monitor turns greyscale...as if I'm looking at the blue "channel" in photoshop or something. Is this normal...meaning normal for a "blue only" mode to be in greyscale rather than in litteral blue? |
November 9th, 2004, 07:11 PM | #4 |
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D93 (9300 Degrees Kelvin) is too bright. The gray scale, especially the highlights will be off. "Blue Only" turns only the blue gun on (red and green are turned off). Lacking the red and green parts of the spectrum, only a gray scale can be made. In "Blue Only" look at the different color temps and you'll see what I mean when I say the gray scale changes.
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November 9th, 2004, 07:25 PM | #5 |
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Isn't the "brightness" or luminance set using the pluge area of the color bars? I ask because to me D93 doesn't look like it's making it "brighter" but the overall color seems cooler and more neutral. With D65 it feels too warm and I 50% grey looks like it has a yellowish/redish cast.
Is there somewhere online I can read up about D93 and D65? I'm worried if I use D65 I'll be color correcting my footage trying to remove the "color cast" that I'm seeing in the greys. |
November 9th, 2004, 07:39 PM | #6 |
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D65 and D50 are standard daylight color temperatures. D93 is not daylight and is considered uncalibrated. The pluge is used to adjust the monitors brightness.
This link might help. The problem is your eyes are used to viewing uncalibrated monitors. It will take a couple of days for your eyes to adjust to D65, then you'll be fine.
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November 9th, 2004, 08:14 PM | #7 |
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This is driving nuts...so bear with me...lol.
Isn't a production monitor supposed to give you the most accurate portrayal of color. In other words a perfect 50% grey should look neutral- without a yellow or bluish cast? Well at D65 50% grey most definitly is too warm. It isn't a flat neutral grey. D93 gives me greys that are perfectly...well..."grey" without a color cast. Would it behove me to keep it at D93...and will if negatively affect my output- and if so how? TIA |
November 9th, 2004, 08:28 PM | #8 |
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Glen, did you read the link? The NTSC spec is D65, daylight. When I look at a D93 color temp. I don't see neutral gray, I see blue-gray. I think your just not accustomed to seeing correct colors.
This is a quote from an unknown source on the internet. The article was emailed to me by a student a year or two ago. This and the next several paragraphs revolve around a simple yet very important question; how white is white, how black is black? If you're hardware isn't set to show whites and blacks properly without any distortion or unwanted shading, any attempt to make accurate color corrections to your videos is nearly impossible which is why proper calibration is so important. Everyone knows when you take photographs or shoot video outdoors, colors look 'different' then they do indoors under artificial lighting, noticeably so in skin tones for example. Under certain lighting conditions colors look more bluish (cooler) or yellowish and warmer. You knew all that. What you may not have known is in an effort to make television pictures brighter, many television sets straight from the factory have a white point of 9300K (Kelvin) or higher while the broadcast standard is only 6500K. Your computer monitor may have yet another color temperature setting, a good reason why you don't want to adjust your video colors and brightness levels by looking directly at your computer monitor, because in part the default color temperature probably isn't 6500K, so if it isn't it will cause all your video colors to be distorted if you adjust off your computer monitor which is why you're much better off using an external monitor to make such adjustments, but only after said monitor is properly calibrated which this tutorial is all about. I'm not sure how else to tell you this Glen, but D65 is correct for a calibrated monitor and D93 is wrong. It's possible the color temp on your monitor is off. I've seen this occasionally , but not too often. Having an uncalibrated monitor will effect the color of the video you produce. If you can see a color difference between D65 and D93, then your productions will reflect a color difference also.
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November 9th, 2004, 09:10 PM | #9 |
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I've read that consumer televisions are shipped with a default color temp of migh higher than 65k. Thus the reason 65k looks so darn yellow to me.
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November 11th, 2004, 04:41 PM | #10 |
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In the USA the standard white point color temperature for TV is 6500K. The Japanese manufacturers found that consumers in that country prefer a bluer white hence Japanese sets made for that market use a 9300K white point. Thus if you are working in the US D65 is the correct setting. If working in Japan (and Sony is a Japanese company) D93 is right.
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November 11th, 2004, 08:26 PM | #11 |
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Not sure if this confuses you more but...
Your eye constantly adjusts its white balance. This is why you normally don't notice color temperature differences when going from one environment to another. However, if you're in a mixed lighting environment, you can notice that at least one light source is not white. I suggest you turn off all the lights in your room. If you have windows, block them off or wait until the afternoon when white balance is close to 6500. You can also wait until nighttime, where there should be little light to interfere with your eye's white balance. After you've done that, put a grayscale image onto your monitor. It should not have a tint to it. If it does, your monitor's not very accurate unfortunately. |
November 11th, 2004, 10:10 PM | #12 | |
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6500 is more the temperature of light on a sunny day at noon, not afternoon. The color temperature drops below 5000 in the afternoon as the suns rays pass through more atmosphere.
Quote:
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November 11th, 2004, 10:25 PM | #13 |
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FWIW, my Sony WEGA TV's have a "color temp" menu item with three choices: Cool, Neutral and Warm. The manual does not offer any explanation of what the actual color temperatures are. I leave them set to neutral myself...
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November 12th, 2004, 02:00 AM | #14 |
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Yes I have a Sony WEGA XBR HDTV 36". In all preset user modes it has these three settings. I keep mine at neutral as well. I did tests today and Neutral on my WEGA TV looks identical to the greys on my production monitor at D93.
However if I turn it to "Warm" on the TV it then looks identical to D65. ?!?!?!?! I figure if I'm going to be delivering DVDs to clients whose televisions are set to D93 from the factory I should be editing in a D93 space...regardless of whatever the "US spec" is. I don't know how "official" it is if practically every television is set at the Japanese spec of D93. I figure it's correct enough If I balance my chroma and phase using the color bars in blue only mode. And...luminance using the pluge bars. Can't be that far off spec...the bars in blue only match up quite nicely. |
November 12th, 2004, 07:23 AM | #15 |
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Jeff,
Apparently I got that from Poynton's book. Pages 224 and 255 both have discussions of this subject. My read is that many manufacturers of TV sets have traded brightness for accuracy and thus ship sets set for 9300. He is of the opinion that's "too much blue for acceptable color reproduction in Europe or America" but then goes on to say that in Asia there is a cultural preference for more blue and that D93 is common there and that studio monitors in Japan are set up that way. He does not state that any standard requires this setting so when I said D93 was "correct" in Japan that would be per common practice (though their standards might require D93 as well - I've never seen them). |
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