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Plasma vs LCD vs LED for external monitoringPosted by J.Corbett
I searched and did not find this on the web or this forum.
I have a Insignia LCD 720p external monitor. I want a new one with full HD but i want a good one. I am looking to spend 400. - 700. USD for a new one (26 - 37 inch preferring smaller) So which is best? LED / Plasma / LCD Does size really matter? What would you recommend? """ What you do with what you have, is more important than what you could do, with what you don't have." > > > Knowledge + Action = Wisdom - J. Corbett 1992 """"
For the size, it's all about distance, checkout this viewin' distance calculator
[myhometheater.homestead.com]
"More vibrant" color doesn't mean better monitoring.
BT.709 specifies the R,G,B primaries that broadcast monitors aim to match. Since the primaries in BT.709's time had to be filterings of white light, B and G had to be located well inboard the chromaticity diagram, so R,G,B couldn't make a very large triangular gamut. LCD monitors can have R,G,B primaries pretty close to BT.709 specification. I tested my LCD Samsung 305T, see here, and was disappointed, but the gamut match can be worse with LEDs. LED R,G,B primaries are not filterings of white light, so they can be located practically on the boundary of the chromaticity diagram, making a much larger triangle than BT.709 specification, and much larger than any non-LED monitor. Since cameras' sensors are designed, and the signals coded, pretty much with BT.709 primaries in mind I doubt that the video you're editing includes information about world-colors of vibrance which should display outside the BT.709 triangle. Very vibrant looking display of video is false, distorted display. A monitor capable of extra-vibrant colors requires a color profile which avoids those colors for video. The human eye is good at adapting to different monitor brightnesses and even hue shifts, but not to saturation distortion. By using a monitor that gives video extra vibrance you risk judging some bad shots good and some good shots bad, and making wrong editorial decisions. Dennis Couzin Berlin, Germany
Ok, first off LED and LCD are the same TV. They both have an LCD panel on the front.
LED refers to the lighting that is behind the panel. The standard LCD has a fluoresent backlight while the LED has an LED backlight. We have both LED and fluoresent backlight monitors from Flanders Scientific in our shop. For large screen viewing we only use Panasonic Plasma screens. Black levels are far superior on these than any LCD I've seen and of course the viewing angle is nearly 180 degrees so it doesn't matter where the client and editor are sitting, the image looks the same. Walter Biscardi, Jr. Biscardi Creative Media biscardicreative.com
Walter, there are two kinds of white LED. One uses a blue LED to excite a yellowish phosphor. The result is a broadband white light. The other uses red, green, and blue LEDs. The result is a white light composed of three narrow spikes. If the LED backlight is of the second kind then the red, green, and blue filters in the LCD panel become irrelevant. The panel emits three narrow spikes and the color gamut is accordingly enlarged.
If LED backlit displays are claimed to more vivid than fluorescent backlit displays it points to the white LED being of the second kind. If Flanders Scientific is using this backlight in a broadcast reference monitor then for video they are surely imposing a color profile which effectively restricts the gamut to the BT.709 gamut. (There's no harm having too big gamut to start with.) Dennis Couzin Berlin, Germany
D,
With regards to "uses a blue LED to excite a yellowish phosphor". Would that be what is mentioned with this LCD when you scroll down to "Features: Quad Picture Technology"? [www.sharpusa.com]
S, No No. Use of a fourth primary, yellow, is separate from the lightsource matter. Three primaries, generally red, green, blue produce a triangular gamut. Look at the CIE chromaticity diagram. Every triangle you draw in it will omit important chromaticities. Sharp is adding a fourth primary, yellow, to produce a quadrilateral shaped gamut, which fills out the chromaticity diagram better. The advantage of four (and more) primaries for display and reproduction is a very old idea. Some DLP projectors use color wheels with four primaries. (I think my NEC HT1100 did this without saying so.)
While 3-color sensing is enough to see (and record) all colors, 3-color display isn't enough to present all colors. J.C. Maxwell discussed this already in the 1850s. The problem with our technology is that the 3-color sensing by the video camera ends up coded with a limitation for 3-color display. RGB codecs have to be limited to that, but Y'CbCr really don't. For example, by making Y' large, Cb very small, and Cr middling you can force a negative value for B, while R and G are large. That is you can code a yellower yellow than RGB allows. Broadcast safe filters clip that Y'CbCr but they needn't, and shouldn't, if your display will be better than 3-color. Dennis Couzin Berlin, Germany
Ok if i am getting this right....
the plasma is best to externally monitor. A plasma with a 4th primary would be better than basic RGB. """ What you do with what you have, is more important than what you could do, with what you don't have." > > > Knowledge + Action = Wisdom - J. Corbett 1992 """"
JCorbett, that's not my view. A fourth display primary offers the potential of better color but is wasted with video in its present form.
My point is that having a wider gamut (more vivid) display is not a good idea for video editing. The player+graphics card which accesses more of the gamut than contained in the BT.709 triangle is distorting the video's colors. Plasma displays have better black than LCD but not greater color gamut. In fact the plasma phosphors come pretty close to the BT.709 primaries, which is better. Dennis Couzin Berlin, Germany
>The player+graphics card which accesses more of the gamut than contained in the
>BT.709 triangle is distorting the video's colors. One point here is not to use the output from the graphics card. The RGB output from FCP doesn't use managed color spaces. ![]() www.strypesinpost.com
strypes, Unmanaged RGB output directly controls the RGB primaries of the display. 255 means primary full on; 0 means primary full off. If the display is an extra-vibrant type, with its primaries well outside the BT.709 triangle, then the video is seen in distorted color. Unmanaged output is no solution. Correctly managed output is the solution.
Dennis Couzin Berlin, Germany
Not your neighborhood LUT expert, but yes, instead use an IO device to send a 10 bit BT. 709 Y'CbCr signal via SDI to a properly calibrated broadcast monitor which applies a proper LUT for viewing an HD signal.
One interesting point to note is that I have heard of color discrepancies when sending the signal via Y'CbCr HDMI. I am curious why it is so. ![]() www.strypesinpost.com
strypes, the HDMI interface includes a bevy of conventions. The Wikipedia article mentions a "Gamut Metadata Packet" which carries color space information. It's easy to imagine the device at one or the other end of the HDMI connection erring with that packet.
SDI is happily simpler. Dennis Couzin Berlin, Germany
This is interesting...I just started learning about OLED Monitors:
[pro.sony.com] When life gives you dilemmas...make dilemmanade. ![]()
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