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post #181 of 261 Old 11-18-2004, 02:24 PM
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Originally posted by xrox
Yes the are as far as light production (photoluminescence vs cathodluminescence). However as far as pixel addressing DLPs and Plasma are nearly identical and CRT is in a class by itself.
How so? Wired vs arc?

All of individual pixel function on any of these devices is unique in their own way(or they wouldnt different devices) but what is the huge gulf that seperates CRT again?

Thats my point, I know the screen is not that different(vs say plasma.) I know the screen can be effectively addressed even though its wireless. I just dont see CRTs in one class and everything else in another.

ss
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post #182 of 261 Old 11-18-2004, 02:36 PM
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Originally posted by dt_dc
First off, though, to the plasma.

You can't make a 'Multiscan Plasma'. Everything has to go to it's native rate. Yes ... a plasma cell is coated with phospor. There's where the similarity ends. You can not get 1/2 a plasma cell to release bright light ... and the other 1/2 to release no light. The phosphor material itself can do that, but a plasma cell can't. The plasma in the cell is charged ... releases ultraviolet ... evenly ... phosphor emits light ... very evenly and consistantly across the entire cell.
Multiscanning is a compromise on a CRT no matter how you slice it. To my ear you are arguing something that is a misuse of a devices display potential defines its character. CRTs also only do this in the horizontal not the vertical. It solves lower line counts vertically by turning them off. A serious compromise of screen real estate.

A devices character shouldnt be defined by misuse IMO. I am sure given enough time I could think of all sorts of nasty things I could do to misuse a plasma or DLP, but what would be the point if the best picture is the goal?

A CRT IMO should be driven to its maximum resolution progressively at a 1 pixel per triad relationship. Anything else shouldnt be on the table and definitely shouldnt define the display.

I also am failing to see how a plasma couldnt light a portion of a pixel if you had that control of the panel? Just because it isnt built that way doesnt mean it couldnt be done.

I'll say again, the best thing fixed pixel devices brought was NR resolutions. CRTs would so benefit too.

ss
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post #183 of 261 Old 11-18-2004, 02:37 PM
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Quote:
Originally posted by subysouth
How so? Wired vs arc?

All of individual pixel function on any of these devices is unique in their own way(or they wouldnt different devices) but what is the huge gulf that seperates CRT again?

Thats my point, I know the screen is not that different(vs say plasma.) I know the screen can be effectively addressed even though its wireless. I just dont see CRTs in one class and everything else in another.

ss
Apart from the whole "fixed pixel or addressable pixel" CRT argument we have there is this:

CRT's use a continuous waveform that uses amplitude to vary the voltage which in turn varies the electron energy to the phosphor to give greyscale (analog and linear)

Plasma, DLP must use a constant (square wave) pulse voltage to turn pixels on or off. they Cannot vary the voltage to produce grayscale like CRTs do. they must use PWM or ADS.

This is a huuuuuuuuge advantage for CRT!!!!!!!!!!! Just huge!

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post #184 of 261 Old 11-18-2004, 02:58 PM
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Originally posted by subysouth
I am also confused by why you think you the outcome of displaying red on a plasma or a CRT is different even after your explanation? What exact thing can you do on a CRT but not a plasma? I must have missed it.
where the X is some shade of red ... and the dots are some other shade of red (or black):
+--------+
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|.............|
|.............|
|.............|
+--------+
In the individual Red Dot of a CRT triad ... the above is possible.

In the individual Red Dot (subpixel, cell) of a plasma triad (pixel) ... the above is not possible.

This is the heart of digital vs. analog ... multiscan vs. fixed panel ...

I'm not saying either is "better" ... fact is, they are both compromises ...

However, this is why they are different.
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post #185 of 261 Old 11-18-2004, 03:09 PM
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Quote:
Originally posted by dt_dc
where the X is some shade of red ... and the dots are some other shade of red (or black):
+--------+
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|.............|
|.............|
|.............|
+--------+
In the individual Red Dot of a CRT triad ... the above is possible.

In the individual Red Dot (subpixel, cell) of a plasma triad (pixel) ... the above is not possible.

I've seen this with my scope :) partial excitation of a dot

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post #186 of 261 Old 11-18-2004, 03:16 PM
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Quote:
Originally posted by xrox
Apart from the whole "fixed pixel or addressable pixel" CRT argument we have there is this:

CRT's use a continuous waveform that uses amplitude to vary the voltage which in turn varies the electron energy to the phosphor to give greyscale (analog and linear)

Plasma, DLP must use a constant (square wave) pulse voltage to turn pixels on or off. they Cannot vary the voltage to produce grayscale like CRTs do. they must use PWM or ADS.

This is a huuuuuuuuge advantage for CRT!!!!!!!!!!! Just huge!
Still not seeing a seperate class based on this. Especially not defined as one fixed-pixel the other not. Just semantics to me.

But anyway its cool. I'm going go on believeing all device are fundamentally fixed resolution and all should be fixed pixel. And as "unfixed-pixel" as CRT is could be effectively replicated on most other devices.

ss
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post #187 of 261 Old 11-18-2004, 03:20 PM
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Quote:
Originally posted by dt_dc
where the X is some shade of red ... and the dots are some other shade of red (or black):
+--------+
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|.............|
|.............|
|.............|
+--------+
In the individual Red Dot of a CRT triad ... the above is possible.

In the individual Red Dot (subpixel, cell) of a plasma triad (pixel) ... the above is not possible.

This is the heart of digital vs. analog ... multiscan vs. fixed panel ...

I'm not saying either is "better" ... fact is, they are both compromises ...

However, this is why they are different.
There is no way a human eye is defining half a phosphor dot. If you can, you are to close to be appreciating any of the actual picture image in its entirety. All your eye is seeing is some level of x red output. This net result is easily replicatable on a plasma of equal resolution.

ss
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post #188 of 261 Old 11-18-2004, 03:22 PM
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"All display devices ultimately produce analog images or your eyes wouldnt see them."

I don't believe that is correct for DLP sets. The image it produces is digital (based upon the state of the micromirror). However it does it so fast that the eye sees this digital light signal (because of retention in the eye) as a normal display.
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post #189 of 261 Old 11-18-2004, 03:48 PM
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Originally posted by PaulGo
"All display devices ultimately produce analog images or your eyes wouldnt see them."

I don't believe that is correct for DLP sets. The image it produces is digital (based upon the state of the micromirror). However it does it so fast that the eye sees this digital light signal (because of retention in the eye) as a normal display.
There is no such thing as digital visible light. Digital in this case means composed of numbers, your eyes dont see numbers of a digital image. There can be a visible reproduction of a digitally rendered description of a light.

ss
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post #190 of 261 Old 11-18-2004, 03:50 PM
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Quote:
Originally posted by subysouth
There is no way a human eye is defining half a phosphor dot. If you can, you are to close to be appreciating any of the actual picture image in its entirety. All your eye is seeing is some level of x red output.
Correct ... but the above is the difference between analog and digital. This is why you can't make an 'analog' plasma. Or a plasma with multiple native scan rates.

That difference of on/off (digital) vs. (in theory, infinitively resolvable) analog is very important when we get to ...
Quote:
Originally posted by subysouth
This net result is easily replicatable on a plasma of equal resolution.
Not really ... you'd think so ... but it's not ... each approach has it's advantages / disadvantages ... they're just plain different ... but this is where things get extremely complicated and I'm going home for the night.
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post #191 of 261 Old 11-18-2004, 04:30 PM
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Quote:
Originally posted by subysouth
There is no way a human eye is defining half a phosphor dot. If you can, you are to close to be appreciating any of the actual picture image in its entirety. All your eye is seeing is some level of x red output. This net result is easily replicatable on a plasma of equal resolution.

ss

This is ABSOLUTELY wrong wrong wrong wrong.......

Just get a scope and look at a dot mask and you'll see half dots and the like. Look for text, it's really easy to spot partial dots.

Jesus, just go an look at an analog CRT with HUGE DOTS and you will see it with the naked eye.

Just because you send an electron to the red stripe in a sony monitor doesn't mean the whole thing lights up?

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post #192 of 261 Old 11-18-2004, 04:39 PM
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Originally posted by xrox
This is ABSOLUTELY wrong wrong wrong wrong.......

Just get a scope and look at a dot mask and you'll see half dots and the like. Look for text, it's really easy to spot partial dots.

Jesus, just go an look at an analog CRT with HUGE DOTS and you will see it with the naked eye.

Just because you send an electron to the red stripe in a sony monitor doesn't mean the whole thing lights up?
Not wrong....

You dont watch tv with a scope. I am not doubting it happens, your eyes just dont register it at normal viewing distance. If you are spotting partial dots youre about 3x too close to the screen and are losing coherent total image.

ss
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post #193 of 261 Old 11-18-2004, 04:44 PM
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Originally posted by dt_dc
Correct ... but the above is the difference between analog and digital. This is why you can't make an 'analog' plasma. Or a plasma with multiple native scan rates.

That difference of on/off (digital) vs. (in theory, infinitively resolvable) analog is very important when we get to ...Not really ... you'd think so ... but it's not ... each approach has it's advantages / disadvantages ... they're just plain different ... but this is where things get extremely complicated and I'm going home for the night.
The net affect is very similar I think.

Picture two 34" sets, one plasma one crt, with equal ultimate(triads to pixels) resolution. Figure 852x480 on both. Partially expose the red phosphor in a dot on one screen say 75% coverage and drive the plamas identical location pixel at 75% of red.

Net result at normal distance is equal IMO. Cant see it coming out any different or any difference would be esoteric. It think a lot of the difference we think we would see come from little or no overlap in screen sizes and pixels of these technologies. We're mentally comparing apples and oranges.

ss
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post #194 of 261 Old 11-18-2004, 04:46 PM
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Originally posted by subysouth
Not wrong....

You dont watch tv with a scope. I am not doubting it happens, your eyes just dont register it at normal viewing distance. If you are spotting partial dots youre about 3x too close to the screen and are losing coherent total image.

ss

actually I was about 60x too close....LOL

point taken :)

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post #195 of 261 Old 11-18-2004, 04:48 PM
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Originally posted by xrox
actually I was about 60x too close....LOL

point taken :)
LOL. Now that I am thinking about can you even say x times too close?

ss
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post #196 of 261 Old 11-18-2004, 04:55 PM
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Originally posted by subysouth
LOL. Now that I am thinking about can you even say x times too close?

ss
If I were to believe my mother about sitting too close, then at 60x not only would I go blilnd but fry my brain in the process..........:)

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post #197 of 261 Old 11-18-2004, 09:09 PM
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Quote:
Originally posted by xrox
SID Journal Volume 11 number 3 pp467 (Fast - Intelligent - Tracking CRT)

As I said before it's the size of a buick!!!!! :)

However, normal CRTs are not pixel addressed period!

Cheers
Thank you for the reference. I located it on the web. I will read it when I get time and want to spend $20 to get it.

I agree, normal CRTs are not pixel addressed, period!

Dave
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post #198 of 261 Old 11-19-2004, 07:28 AM
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"There is no such thing as digital visible light. Digital in this case means composed of numbers, your eyes dont see numbers of a digital image. There can be a visible reproduction of a digitally rendered description of a light.

ss"

Digital means an on or off state not numbers. Analog means a variable state between on and off. The DLP mirrors are digital meaning they either shine toward the light or away from the light. The DLP can only be digital but it is the amount of time toward the light vs the amount of time away from the light that determines the shading. Again DLP is digital - the human eye takes these digital images and makes it into something it can see.
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post #199 of 261 Old 11-19-2004, 08:28 AM
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Quote:
Originally posted by subysouth
There is no way a human eye is defining half a phosphor dot. If you can, you are to close to be appreciating any of the actual picture image in its entirety. All your eye is seeing is some level of x red output. This net result is easily replicatable on a plasma of equal resolution.

ss
It's not the individual phosphor dots that are seen, it's the net result of those phosphor dots that makes the partial exitation noticable. I for one first noticed the digital way of scaling when viewing an lcd monitor of 17 inches from about 7-9 feet away while looking over a friend's shoulder. As I later discovered, he had the desktop res at 1024x768 on a 1280x1024 display. Up until that point, I had assumed digital displays worked pretty much the same as crt's, and would yield the same picture results at various resolutions. I wasn't able to see individual pixels from the distance, but still noticed the "all or nothing" nature of the pixels (when I wasn't even looking for it!). What I don't understand is how you can honestly say partial exitation on a crt phosphor is no different from a plasma pixel's red being underdriven. Lightwise yes, but it's the fact that the phosphor on the crt can be partially lit in different areas that makes them different.

The net result of this effect can be very noticeable, otherwise, I don't think so many people (not only on this forum) would make it a point to consider it an advantage (or at least a difference) to digital displays. I actually never noticed the effect until I saw what digital displays do to scale images on that 17 inch monitor...:( Not that digital displays are necessarily horrible at it, but it was enough to show me that there were indeed differences between CRT's and digital displays-ones that to me were worth considering before I just blindly drop a few grand on a flat panel :) Now, even with the known resolution deficiency and geometry problems, I have the xbr960 at the top of my list :)

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post #200 of 261 Old 11-19-2004, 10:25 AM
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Quote:
Originally posted by PaulGo
"There is no such thing as digital visible light. Digital in this case means composed of numbers, your eyes dont see numbers of a digital image. There can be a visible reproduction of a digitally rendered description of a light.

ss"

Digital means an on or off state not numbers. Analog means a variable state between on and off. The DLP mirrors are digital meaning they either shine toward the light or away from the light. The DLP can only be digital but it is the amount of time toward the light vs the amount of time away from the light that determines the shading. Again DLP is digital - the human eye takes these digital images and makes it into something it can see.
Digital does not mean on or off. You need to look up the various definitions of digital.

Digitial in the sense you are using it means composed of numbers. Digital info can not be seen by the human eye. The effects of digital control of analog light creating device can be seen by the human eye.

Computers "see" digital image data, humans do not.

ss
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post #201 of 261 Old 11-19-2004, 10:34 AM
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Quote:
Originally posted by Geise
It's not the individual phosphor dots that are seen, it's the net result of those phosphor dots that makes the partial exitation noticable. I for one first noticed the digital way of scaling when viewing an lcd monitor of 17 inches from about 7-9 feet away while looking over a friend's shoulder. As I later discovered, he had the desktop res at 1024x768 on a 1280x1024 display. Up until that point, I had assumed digital displays worked pretty much the same as crt's, and would yield the same picture results at various resolutions. I wasn't able to see individual pixels from the distance, but still noticed the "all or nothing" nature of the pixels (when I wasn't even looking for it!). What I don't understand is how you can honestly say partial exitation on a crt phosphor is no different from a plasma pixel's red being underdriven. Lightwise yes, but it's the fact that the phosphor on the crt can be partially lit in different areas that makes them different.

The net result of this effect can be very noticeable, otherwise, I don't think so many people (not only on this forum) would make it a point to consider it an advantage (or at least a difference) to digital displays. I actually never noticed the effect until I saw what digital displays do to scale images on that 17 inch monitor...:( Not that digital displays are necessarily horrible at it, but it was enough to show me that there were indeed differences between CRT's and digital displays-ones that to me were worth considering before I just blindly drop a few grand on a flat panel :) Now, even with the known resolution deficiency and geometry problems, I have the xbr960 at the top of my list :)
Geise the part that is confusing things is the assumption that there are more phosphor dots on a CRT than a plasma.

Picture an identical number of red phosphor dots and red portions of plasma phosphor with essentially identical location on two different screens.

Even though the plasma drives its entire area at a percentage rate and the CRT drives a portion of its phosphor fully at an area percentage rate, the net effect is identical. Your eye at normal viewing distance MIGHT(if its pure red - if its driving to white it will see white) see red at that triad location but there is absolutely no way your eye is seeing which side of the phosphor dot is not lit. Therefore it has no way of using that as a definition characteristic. Your eye is likely not even defining to the phosphor dot(it shouldnt be if youre at the appropriate viewing distance.)

So red at x %coverage on y location phosphor dot on a CRT vs red at x %drive at y location on a plasma, look identical to the human eye if all other things are equal. If youre seeing a difference youre WAY too close.

What I beleive you are doing is comparing sets of varied pixels sizes and screen sizes and resolution and thats not a fair comparison.

ss
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post #202 of 261 Old 11-19-2004, 10:52 AM
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Quote:
Originally posted by subysouth
The net affect is very similar I think.

Picture two 34" sets, one plasma one crt, with equal ultimate(triads to pixels) resolution. Figure 852x480 on both. Partially expose the red phosphor in a dot on one screen say 75% coverage and drive the plamas identical location pixel at 75% of red.

Net result at normal distance is equal IMO. Cant see it coming out any different or any difference would be esoteric.
Ok ... but now let's feed those two systems a 1920x1080 image. Let's say the image is a completely black screen with a single pixel horizontal white line running accross it.

With that lowly 852x480 masked CRT ...

http://members.cox.net/dt_dc/TriadsFinal.GIF
(Image 1)

Assuming it's able to do a 1920x1080i scan rate ...

You get:

http://members.cox.net/dt_dc/TriadsSplit.GIF
(Image 2)

Or maybe:

http://members.cox.net/dt_dc/TriadsPartial.GIF
(Image 3)

As you pointed out above ... The eye will see this as a single white line accross the screen. It's not perfect, but it's close. Wow, that 852x480 mask has resolved a single pixel line in a 1920x1080 image ... pretty cool.

Ok, now lets feed the exact same 1920x1080 image to our digital display.

Now, somewhere we have to digitally scale that image from 1920x1080 to 852x480. Maybe the display is smart enough to do it ... maybe we have an external scaler / STB / whatever. We have to get rid of 63% of our 1080.

Let's assume a very simplistic scaler that just drops the rows/pixels. I think that's every other row dropped ... every nine rows you have to drop an extra pixel. What if that line just happens to be on a row that's been dropped? The digital display will show:

http://members.cox.net/dt_dc/TriadsBlack.GIF
(Image 4)

Surely the eye is ging to see a (pretty major) difference?

BUT WAIT you say. Digital scaling doesn't just drop pixels! There's interpolation algorithms ... edge / trasition algorithms ... motion adaptive algorithms ... all kinds of fancy ways to get that 1080 -> 480 in a way that should look pretty close to the orignal.

Yes ... but if you know the algorithms ... you can always come up with a source image that won't look quite 'right'.

Say you have 480 evenly spaced white lines accross that 1920x1080 image. The CRT will give you ... 480 white lines while the digital panel will give you ... a solid gray screen? Again ... pretty major difference.

Note: Images above are on a Personal Web Space with bandwith limits ... let me know if they fail to load and I'll find a new home.
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post #203 of 261 Old 11-19-2004, 10:58 AM
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Quote:
Originally posted by subysouth
Digital does not mean on or off. You need to look up the various definitions of digital.

Digitial in the sense you are using it means composed of numbers. Digital info can not be seen by the human eye. The effects of digital control of analog light creating device can be seen by the human eye.

Computers "see" digital image data, humans do not.

ss
You are incorrect a zero or one is the equivalent of on or off. A human does see lightwaves but the source can be digital. Numbers are digits a computer does not understand numbers only on or off sequences that allow electrons to flow or not flow through a transistor. Below is the definition of digital:

Describes any system based on discontinuous data or events. Computers are digital machines because at their most basic level they can distinguish between just two values, 0 and 1, or off and on. There is no simple way to represent all the values in between, such as 0.25. All data that a computer processes must be encoded digitally, as a series of zeroes and ones.

In general, humans experience the world analogically. Vision, for example, is an analog experience because we perceive infinitely smooth gradations of shapes and colors. Most analog events, however, can be simulated digitally. Photographs in newspapers, for instance, consist of an array of dots that are either black or white. From afar, the viewer does not see the dots (the digital form), but only lines and shading, which appear to be continuous. Although digital representations are approximations of analog events, they are useful because they are relatively easy to store and manipulate electronically. The trick is in converting from analog to digital, and back again.



http://isp.webopedia.com/TERM/D/digital.htm
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post #204 of 261 Old 11-19-2004, 11:33 AM
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Originally posted by PaulGo
You are incorrect a zero or one is the equivalent of on or off. A human does see lightwaves but the source can be digital. Numbers are digits a computer does not understand numbers only on or off sequences that allow electrons to flow or not flow through a transistor. Below is the definition of digital:

Describes any system based on discontinuous data or events. Computers are digital machines because at their most basic level they can distinguish between just two values, 0 and 1, or off and on. There is no simple way to represent all the values in between, such as 0.25. All data that a computer processes must be encoded digitally, as a series of zeroes and ones.

In general, humans experience the world analogically. Vision, for example, is an analog experience because we perceive infinitely smooth gradations of shapes and colors. Most analog events, however, can be simulated digitally. Photographs in newspapers, for instance, consist of an array of dots that are either black or white. From afar, the viewer does not see the dots (the digital form), but only lines and shading, which appear to be continuous. Although digital representations are approximations of analog events, they are useful because they are relatively easy to store and manipulate electronically. The trick is in converting from analog to digital, and back again.



http://isp.webopedia.com/TERM/D/digital.htm
Nope, a one or a zero equals nothing. Computers say ones and zeros equal off and on. You could make a computer that says 2 is off and 5 is on.

There is no such thing as a "1" or "0" they are terms devised by humans for counting things.

Digital means composed of numbers not composed of ones and zeroes. If your eyes could see digital it would see the 1 or 0 and register off or on. Your eyes dont see digital data. It sees a visible light representation of what you can encode as digital data. Just because DLP employs ones and zeroes doesnt mean the light it makes is digital.

I am sorry if you cant understand that. All human vision is analog, so all display output is analog.

ss
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post #205 of 261 Old 11-19-2004, 11:40 AM
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Quote:
Originally posted by dt_dc
Ok ... but now let's feed those two systems a 1920x1080 image. Let's say the image is a completely black screen with a single pixel horizontal white line running accross it.

With that lowly 852x480 masked CRT ...

http://members.cox.net/dt_dc/TriadsFinal.GIF
(Image 1)

Assuming it's able to do a 1920x1080i scan rate ...

You get:

http://members.cox.net/dt_dc/TriadsSplit.GIF
(Image 2)

Or maybe:

http://members.cox.net/dt_dc/TriadsPartial.GIF
(Image 3)

As you pointed out above ... The eye will see this as a single white line accross the screen. It's not perfect, but it's close. Wow, that 852x480 mask has resolved a single pixel line in a 1920x1080 image ... pretty cool.

Ok, now lets feed the exact same 1920x1080 image to our digital display.

Now, somewhere we have to digitally scale that image from 1920x1080 to 852x480. Maybe the display is smart enough to do it ... maybe we have an external scaler / STB / whatever. We have to get rid of 63% of our 1080.

Let's assume a very simplistic scaler that just drops the rows/pixels. I think that's every other row dropped ... every nine rows you have to drop an extra pixel. What if that line just happens to be on a row that's been dropped? The digital display will show:

http://members.cox.net/dt_dc/TriadsBlack.GIF
(Image 4)

Surely the eye is ging to see a (pretty major) difference?

BUT WAIT you say. Digital scaling doesn't just drop pixels! There's interpolation algorithms ... edge / trasition algorithms ... motion adaptive algorithms ... all kinds of fancy ways to get that 1080 -> 480 in a way that should look pretty close to the orignal.

Yes ... but if you know the algorithms ... you can always come up with a source image that won't look quite 'right'.

Say you have 480 evenly spaced white lines accross that 1920x1080 image. The CRT will give you ... 480 white lines while the digital panel will give you ... a solid gray screen? Again ... pretty major difference.

Note: Images above are on a Personal Web Space with bandwith limits ... let me know if they fail to load and I'll find a new home.
Actually you need to see the other thread about 1400 lines on a XBR960. Your graphs we now realize are incorrect. CRTs dont address the lines the way you are posting and even then comparing equal sized plasma pixles to those triads nets the same effect. You are also changing beam spot size which we have no evidence occurs except by compromising somewhere else. Properly calibrated beam spot size does not change. And when you do change beam spot size in the vertical youre gonna do damage in the horizontal too.

ss
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post #206 of 261 Old 11-19-2004, 11:54 AM
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"I am sorry if you cant understand that. All human vision is analog, so all display output is analog.

ss"

I am sorry you cannot understand the concept of what digital means (on or off) but maybe someday I hope you will. I have a degree in programming and I have helped design computer circuits.

Anyway enough of this since we are just repeating ourselves.:rolleyes:
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Originally posted by PaulGo
I am sorry you cannot understand the concept of what digital means (on or off) but maybe someday I hope you will. I have a degree in programming and I have helped design computer circuits.

Anyway enough of this since we are just repeating ourselves.:rolleyes:
Main Entry: dig·i·tal
Pronunciation: 'di-j&-t&l
Function: adjective
Etymology: Latin digitalis
1 : of or relating to the fingers or toes : DIGITATE
2 : done with a finger
3 : of, relating to, or using calculation by numerical methods or by discrete units
4 : of or relating to data in the form of numerical digits
5 : providing a readout in numerical digits <a digital voltmeter>
6 : relating to an audio recording method in which sound waves are represented digitally (as on magnetic tape) so that in the recording wow and flutter are eliminated and background noise is reduced


Dont see anything about off and on there. You are talking about a specific application in one design of computer that is now widespread. Digital has nothing directly to do with that style.

A jpeg image is a digital representation of an analog image. The computer that interprets jpg images may fundamentally operate on an off/on primary structure but that has nothing to do with the encoding of a digital jpg image or the definition of digital.

Youre mistaken.

ss
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post #208 of 261 Old 11-19-2004, 01:08 PM
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Quote:
Originally posted by subysouth
Main Entry: dig·i·tal
Pronunciation: 'di-j&-t&l
Function: adjective
Etymology: Latin digitalis
1 : of or relating to the fingers or toes : DIGITATE
2 : done with a finger
3 : of, relating to, or using calculation by numerical methods or by discrete units
4 : of or relating to data in the form of numerical digits
5 : providing a readout in numerical digits <a digital voltmeter>
6 : relating to an audio recording method in which sound waves are represented digitally (as on magnetic tape) so that in the recording wow and flutter are eliminated and background noise is reduced


Dont see anything about off and on there. You are talking about a specific application in one design of computer that is now widespread. Digital has nothing directly to do with that style.

A jpeg image is a digital representation of an analog image. The computer that interprets jpg images may fundamentally operate on an off/on primary structure but that has nothing to do with the encoding of a digital jpg image or the definition of digital.

Youre mistaken.

ss
I'm afraid your mistaken again :)

the key is in the word discrete (right from your definition)

Of all the flat panel technologies, I think LCD is the only one that can be made into analog. But even that would require a complete overhaul of the electronics.

There were even some analog TFT - LCDs on the market for a while.

Plasma, and DLP must use discrete packets of data to activate the pixels to produce greyscale.

CRT use a continuous analog wave to do the same.

Here is an explanation from the web:

----------------------------------------
2.4 Understanding Digital Color Pixels

4 Bits, 8 Bits, 16 Bits, 24 Bits Just how many colors
can they actually generate ? Digital video divides the number
of colors or gray scales into a distinct number of points.
Based on these "POINTS" the system can generate a fixed number
of colors or gray scales.

COMMONLY ASKED QUESTION NOTE: What is analog video ? Unlike
digital or bit based video analog video is based on a
continuous flow of data. The wave form can be thought of as a
continuous wave of points with the distance between points so
small that it is impossible to differentiate between them. In
other words, it can theoretically provide an infinite number
of gray scales. VGA is an analog system and VGA CRTs are
analog displays. The advantage of an analog display is that
when you upgrade your video card and drivers to handle more
colors, your existing monitor should be able to operate with
the extended color ranges.
------------------------------------------

Analog video is accepted, processed, sourced, and emitted to the pixels all in the analog domain!!!!!

Not so for DLP or Plasma or most LCDs. They use PWM or ADS.

In fact DLPs REQUIRE a A/D converter if you want to feed in composite video.

Over thinking, over analyzing separates the body from the mind
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post #209 of 261 Old 11-19-2004, 01:16 PM
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Quote:
Originally posted by xrox
I'm afraid your mistaken again :)

the key is in the word discrete (right from your definition)

Of all the flat panel technologies, I think LCD is the only one that can be made into analog. But even that would require a complete overhaul of the electronics.

There were even some analog TFT - LCDs on the market for a while.

Plasma, and DLP must use discrete packets of data to activate the pixels to produce greyscale.

CRT use a continuous analog wave to do the same.

Here is an explanation from the web:

----------------------------------------
2.4 Understanding Digital Color Pixels

4 Bits, 8 Bits, 16 Bits, 24 Bits Just how many colors
can they actually generate ? Digital video divides the number
of colors or gray scales into a distinct number of points.
Based on these "POINTS" the system can generate a fixed number
of colors or gray scales.

COMMONLY ASKED QUESTION NOTE: What is analog video ? Unlike
digital or bit based video analog video is based on a
continuous flow of data. The wave form can be thought of as a
continuous wave of points with the distance between points so
small that it is impossible to differentiate between them. In
other words, it can theoretically provide an infinite number
of gray scales. VGA is an analog system and VGA CRTs are
analog displays. The advantage of an analog display is that
when you upgrade your video card and drivers to handle more
colors, your existing monitor should be able to operate with
the extended color ranges.
------------------------------------------

Analog video is accepted, processed, sourced, and emitted to the pixels all in the analog domain!!!!!

Not so for DLP or Plasma or most LCDs. They use PWM or ADS.

In fact DLPs REQUIRE a A/D converter if you want to feed in composite video.
Where am I argiung that a DLP or LCoS is not activated by a digital bit stream?

You might want to read before you start saying people are wrong.

The topic of discussion is is visible light analog or digital, not whether DLP or LCoS is addressed digitally or not. Thanks for clearing that non-topic up for us though. You are a master of stating the obvious.;)

ss

And btw it would be possible to build a functional analog dlp or LCoS chip. There is nothing to say their physical components couldnt be manipulated via analog means. It would also be difficult and pointless, but the possibilty makes you wrong again:p .
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post #210 of 261 Old 11-19-2004, 01:16 PM
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"Youre mistaken.

ss"

You just don't get it. I recommend you take some computer engineering courses. You are not looking at the electronic meaning of digital and how it applies to computers or electronics.
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