These Are Not Pixels: Revisited

In this video, I’d like to revisit a concept
from my television series. I created this thumbnail for my video explaining
analog color TV, and it’s been causing debate ever since. Though I had hoped my video on Trinitron would
help illustrate my point and put the debate to rest, there was and is still much debate
in the comments. It seems this debate comes mostly from semantics,
and I’ll admit I see a gap in my explanation. So let’s try again. This is the TV in my kitchen. Like any TV on sale today, it produces an
image by manipulating the brightness of many thousands (and these days millions) of individual
picture elements called pixels, which is actually just short for picture element. There are a few different technologies in
use these days, but at their core their job is to produce a set brightness value for the
red, green, and blue components of each pixel. These are called subpixels, and in many LCD
panels each subpixel is actually further divided into sub-sub pixels. This probably increases the total number of
discrete brightnesses each color can make, and thus allows for more precise control over
the panel and a larger number of possible colors. Someone please correct me if that’s not
what the subdivisions do. The combination of red, green, and blue can
create what appears to our eyes to be any color, because the way we perceive color (for
those of us with normal trichromatic color vision, anyway) is through the ratio of stimulation
between the three different cone cells in our eyes. Their primary sensitivities are red, green,
and blue, so by using just these three colors, we can activate the cone cells in any given
ratio and thus produce any apparent color. This biology hack is the result of the overlapping
sensitivities of each cone cell. For example, yellow light stimulates both
the red and green cone cells in your eyes roughly equally, as both of these cells can
detect this wavelength of light. This means that to recreate what we see as
yellow light, we don’t need to actually reproduce the same wavelength of light. Instead, we can artificially stimulate the
red and green cone cells with just red and green light, and so long as the red and green
cells receive the same relative stimulation as they did with honest-to-goodness yellow
light, the brain can’t tell the difference and thinks it’s yellow. Simply outputting red, green, and blue light
can produce any color to our eyes because when combined, it can produce the same ratios
of stimulation between the three cone cells that any real color would. Anyway, the microprocessors inside this television
are working together to make it all…happen, and the main image processor can tell the
panel exactly what to do. The image on screen is coming from a Chromecast,
and through the HDMI port on the television, the Chromecast can tell it exactly what each
pixel needs to do to make this image, and the drivers inside the TV will make that happen. We can define the resolution of this display
by counting how many pixels there are along each edge. I’d rather not actually do that, so I’ll
just recite the specs here and tell you that there are 1,366 pixels along the bottom and
768 pixels along the sides, yes I know that’s not 720P but that’s the panel that’s in
here, and that means that there are 1,049,088 pixels on this screen. Generally, resolution is defined as X by Y,
so we’d say this panel has a resolution of 1366 by 768. Now take a look at an old school CRT television. Get nice and close to it and you’ll find
what appear to be pixels. There’s a neat division between red, green,
and blue. The borders are defined, and it’s forming
a grid, almost. But, you would be running a fool’s errand
if you attempted to count the number of these “pixels” along the edges to determine
this TV’s resolution. That’s because these aren’t pixels, and
they don’t define its absolute resolution. To understand why, you need to look at a black
and white television. Oh how convenient, a black a white television. Now with the set turned off, you can’t see
any structure to this screen. Going back to the LCD TV, even when it’s
off, that grid of pixels is still there. You need to shine a bright light onto it to
see them, but the pixels are there as physical parts of the screen. But on this little CRT, there’s no grid
to be seen. Let’s switch it on. With an image now on screen, you should be
able to see a series of lines. In analog video, this is how the image is
drawn. See, the CRT only has one “pixel” to deal
with. At the rear of the picture tube is an electron
gun which is projecting a single point of light at the screen. Then, electromagnets in the deflection yoke
move this point around the screen very rapidly in a pattern called a raster. By varying the brightness of the point of
light as it moves around the screen, an image can be made. The image is drawn as a series of stacked
horizontal lines. In the US, roughly 480 lines are visible on
the screen at once, drawn as two fields of 240 lines 60 times per second as interlaced
video. This is why standard definition is defined
as 480i here in the States. I’ve made a video explaining how analog
television works in greater detail, which can you find up above now or down below later. Now, this TV has no idea what it’s doing. It doesn’t have a microprocessor. It doesn’t have an HDMI port. It doesn’t have any digital circuitry of
any kind. All it’s doing is looking for two pulses
in the video signal, the horizontal blanking interval and the vertical blanking interval,
in order to draw the image in the same place on the screen and not have it roll around
like this. The nature of this signal is analog, and really
all the signal does is tell the TV how bright to make the image. It’s just timed really really well so that
each individual part of the screen is drawn with the correct brightness, as the position
of the point of light is determined by the length of time that has elapsed from the start
of the frame. And to be clear, we’re dealing with tiny
fractions of a second since the beam moves incredibly quickly. So then, here’s the challenge. Where are the pixels? Well, there aren’t any! If I change the channel and we take a look
at snow, you’ll see that there is no regularity whatsoever in this noise. If this image was defined by a grid of discrete
picture elements, the borders between white and black sections should form columns of
some sort, or at the very least there should be some clear vertical structure visible. But there isn’t. They appear completely randomly within the
line. I can tell you exactly where the line is,
but I can’t define any separation within the line itself. That’s completely arbitrary. Now here’s where the color CRT comes into
play. Specifically one like this. This is a GE television, using a slot-mask
CRT. Up close, it appears to have a similar grid
structure to the LCD TV in my kitchen. So then, why aren’t these pixels? They’re what make up the image, right? Well, no, they aren’t. These are actually called phosphor dots. What they do is create specific targets for
the red, green, and blue electron beams to hit. See to make a color image, we need to make
a red, green, and blue image, and they need to be merged together somehow to appear as
one. In the early days of color TV, there were
all sorts of ideas being explored on how to produce an RGB image. I’ll throw another card up on my playlist
on Television, because if this is the sort of thing that interests you you can take quite
the nerdy deep dive. A color CRT is functionally identical to a
black and white CRT, but it draws three separate images at once. Think of it like three picture tubes, one
red, one green, and one blue, combined into a single picture tube. This combined tube has an electron gun for
each color, but of course we also need a way to separate the colors in order to drive each
one on its own. That’s what the phosphor dots do. They separate the face of the tube into a
mosaic of red, green, and blue dots. The earliest color TVs used a pattern of phosphor
dots that looked like this. These dots line up with a simple metal sheet
just behind them. Let me show you what it does. Here I have a green flashlight. If I shine it at this poster board, it creates
a flood of green light. But if I place a mask in front of it with
a single hole, now the light can only make it through in a straight line between the
flashlight and the hole, which produces just a dot on the poster board. Now, here’s a red flashlight. Watch what happens when I put it next to the
green flashlight. Because the red flashlight is in a slightly
different position from the green one, the light it makes can’t take the same path
as the green light. It will go through the hole at a different
angle, so the dot it produces appears next to the green one. Now if I add a third, blue flashlight and
put it in between the red and the green just above them, a blue dot appears below the red
and green dots. If I take the mask away, it creates just a
wash of white light. But with the mask in place, it produces three
small dots of light in the same arrangement as the flashlights themselves, though it’s
mirrored and upside down. If I add a second hole the to mask, the same
pattern appears right next to the first set of dots. If I keep going and make a bunch of small
holes in this offset pattern, what we get is a mosaic pattern of red, green, and blue
dots. This is happening because the flashlights
are arranged in a triangle, and at every hole in the mask the beams converge and cross over
to project the opposite image on the screen. Notice how similar this pattern is to this
color CRT. See, if I aim these three flashlights together
at the poster board, their beams just blend together and make what appears to be white. This is what would happen if we used a color
CRT without a mask. But if I place the mask in front of it, which
is just a piece of aluminum foil with some holes punched in it, suddenly a pattern just
like the phosphor dots appears. Now, the red beam can only hit specific parts
of the screen, and the blue and green beams can’t hit those points. Because the light sources are physically separated,
they can only make their way through the holes at specific angles. The mask puts the red targets in the shadow
of the blue and green beams. The mask casts a shadow on the targets. Wait a minute, shadow mask! What’s important to realize here is that
the mask is what’s creating the pattern of dots. The flashlights are firing indiscriminately
at the mask, but the mask will always force each beam into the correct location on the
other side. This means that no matter what sort of pattern
of light the beams or flashlights are creating, it will always appear as a series of dots
on the other side. So if we go back to our picture tube, what
you see as a viewer are the phosphor dots which are the targets for each individual
color electron beam. Inside the tube, directly behind them, is
the metal sheet with holes in it, which always ensures the color components stay separated
and project onto the phosphor dots in the correct orientation. But the key here is that they do not change
how the image is drawn. Just like the black and white television,
this TV is stacking horizontal lines. In fact, these two televisions are receiving
the same exact signal. The difference is that the color TV can recover
the color information that’s superimposed in the signal through quadrature amplitude
modulation– Don’t worry too much about the specifics of that– and it can then adjust the relative intensities of the three color components. But since that means it’s effectively drawing
drawing three different sets of lines at once, it needs a way to keep the colors from crossing
over. That’s what the shadow mask does. Remember, even though the flashlights were
just blasting away at the mask, the mask made sure each part was separated into little dots
on the other side. From this side of the picture tube, it’s
just like taking a black and white CRT, then drawing a grid on top of it, and then coloring
each little cell in with red green or blue. The only functional difference between a true
color CRT and a black and white CRT with lines and colors drawn on top is that the mask behind
the phosphor dots of the color picture tube ensures the colors stay separated, and thus
allows for individual control of each color. Now, this style of shadow mask makes it hard
to even define what could be a pixel. Assuming each pixel contains one red, one
blue, and one green dot, well first of all they’re triangular, but then each one changes
orientation as you move on and really it’s just a mess but this style of CRT, which uses
a slot-mask display, does make a pattern that really looks like there are pixels. These CRTs arrange the electron guns in a
line, and rather than use a mask with round holes they use a mask with small slots. This allows more of the beam energy to pass
through the mask and makes a brighter image. And here’s where the semantics comes in. I’ll grant you that the picture is “made
up of” these groupings of phosphors. You could say that they are elements of the
picture, and thus are pixels. But this ignores the fact that they are only
there as a side-effect of the need for color separation. They are in front of what makes the image,
and are not the actual building blocks of the image. To put it another way, here’s a window screen. If I put it in front of this album cover,
does that become a pixel? Have I pixellated the image by placing a grid
in front of it? Or have I simply compartmentalized parts of
the image into little square cells? And here’s the part that I think is hardest
to understand. The phosphor dots do not in any way define
the maximum amount of detail that can be displayed on the screen. That may sound silly, but hear me out. All they really do is define the maximum color
resolution of the display. Let’s go back to this CRT. I’ve only shown it in close-up because this
is a laughable little 5 inch color TV boombox from some point in the 1980’s. The dot pitch, that’s the fineness of the
dots, is very poor on this TV. I mean, you can’t really blame it, as it’s
only got 5 inches to work with. This means it can’t display much color detail,
but it can display as much brightness detail as any television. Let me boot up Kingdom Hearts. [PS2 Game Start noise] OK, so take a look at the menu in the bottom
left corner. If we look at the black and white TV, we can
see that there are about 10 or 12 lines defining the height of the letter M in Magic. If we count the number of dots along the height
of the M, we also get about 10, maybe 11. But, each cluster of three color dots spans
the height of two lines. We appear to have only half the color resolution
as we do brightness resolution in this CRT. Look at how infrequently a red dot appears
among blue and green. That’s they key here, we’re not getting
a lot of complete RGB clusters among the word Magic, but we can still clearly see the shape
of the word Magic. You can even see the how the center of the
A is darker than the rest, but only this one red dot is actually darker. But the thing is, from a normal viewing distance,
you can’t really tell how poor the color resolution is. Once you’re far enough away that you can’t
discern the individual phosphor dots, the image appears more or less normally. This is in contrast to a digital LCD panel,
where the pixels themselves define the shape of an image. If I want to draw a letter M using a grid
of 10 X 10 pixels, well I can say how bright I want each pixel to be. Then I can tell the display what to do with
each of these 100 pixels to make an M. But in the case of a CRT, it’s drawing the M
like this, in Lines. That shape is then forced into the grid of
phosphor dots, and wherever it lands will tell you which dots get lit up. And that’s the key difference. In digital video, the pixels define the shape
of the image, logically. In analog video, the shape of the image defines
which phosphor dots are lit. You can see this effect with the small TV. This screen really suffers where very small,
colored elements appear. If I open the pause menu and look at these
stats, some of it is very hard to read. That’s because this text is colored green,
so the blue and red guns pretty much don’t fire when drawing it. Since the green dots are so far apart and
this text is so small, if the text to be drawn lies between the green dots, it just won’t
get drawn. It’s not like the gun isn’t firing, it’s
just that for the entire section here, the text is in the shadow of the green gun, so
none of its energy is able to light up the screen. And that’s the point I’m trying to make
when I say “these are not pixels”. These two TVs are displaying the same image
and they both have 480 lines of resolution. But this little CRT has fewer phosphor
dots, so it can’t recreate color as precisely as the larger TV. But that doesn’t mean it’s not conveying
the same 480 lines of resolution. It is, just in brightness only. It loses detail in the color department, and
as a side-effect it can’t reproduce some fine color details. A CRT television has no control over how the
three electron beams interact with the mask. The combined beam can land and will land wherever
it wants, and it’s then up to the mask to separate the color components. The clusters of phosphor dots are there just
because they need to be. They can be a different size, a different
shape, and some TV’s don’t even split them up beyond vertical stripes. Trinitron. As a final point, which I think is at the
crux of the issue, in an LCD, OLED, Plasma, or any sort of digital display, the grid of
pixels is an active matrix. The display has an electrical connection to
each one of them, and can talk to it. The shadow mask and phopshor dots are a passive
component of the CRT. They don’t get addressed. They don’t have an electrical connection. They’re just there. Sure, the TV does “control” which ones
get lit up, but it’s not done with logical control or any precision whatsoever. Just like the black and white CRT, wherever
the beam lands is what part gets lit up. Now this isn’t to say that an analog TV
can’t produce an image made of pixels. Surely it can, it’s just making small squares. And in fact that’s what it’s been doing throughout all of this video. A PlayStation 2, DVD player, Roku box, or
any digital source with a composite output will take its logical 640X480 digital grid
and convert that to the 480 horizontal lines to drive the TV. But I guarantee you those ethereal pixels
in the logic circuits of the digital source won’t be lining up nicely with these phosphor
dots. They simply don’t need to. Thanks for watching, I hope you enjoyed the
video! If this is your first time coming across the
channel and you liked what you saw, please consider subscribing. As always, thank you to everyone who supports
this channel on Patreon! If you’re interested in making a voluntary
contribution to the channel as well, please check out my Patreon page. There’s a link on your screen or you can
find one down below in the description. Thanks for your consideration, and I’ll
see you next time!

100 Replies to “These Are Not Pixels: Revisited”

  1. This is a fantastic video – one of those explanations where everything just clicks. I was confused about this when I watched the original video but I understand it completely now!

  2. If I can scan 480 rows on a screen with electron beam and if there are 480 rows of slots on shadow mask, then, yeah, there are 480 pixels vertically. Which forces 640 columns to be existed on shadow mask because of the aspect ratio, eventough the beam is continuous. I understand the working principle of television is not pixel based but the result is a pixelated image in the end.

    Everything in the universe, even analog signal results in a 1010 binary fashion. Thats why most of the equations includes a square root expression to normalize the sinus wave.

    Think of an human eye, its maximum resolution is limited by the number of yellow dots placed vertically and horizontally.

    Finally, try to think of the smallest pixel. It would be a single photon hits to a smallest area of any surface. The same thing valid for FPS. It would be the number of photons hit to that tiniest area in one second.

    As a final word, everything appears to be analog is ones and zeros in the end.

  3. The shadow mask should very well define the resolution to some extent though. It does block the beam even in the horizontal lines. The trinitron layout preserves the vertical clarity of the lines perfectly but the horizontal clarity is still restricted by the amount of grills. The electron gun and signal itself also restricts it by losing high frequencies in the analogue circuitry. So the two work together to define the resolution, I think this is the TVL. A more coarse mask means a lower TVL. The other layouts also mask vertically and so it'll naturally inhibit the clarity of the lines as well. A non trinitron shadow mask that is coarser than 480 lines will reduce the apparant vertical resolution. Any shadow mask that is coarser than the frequency of the line will reduce TVL. So it does affect the clarity.

    You can see yourself at 15:08 that it's true. The coarse mask of the right side TV eats up the letters of the menu items even though they are white. Where the finer mask on the left leaves a lot more detail in the white letters.

  4. I assume the shadow mask has to be precisely aligned with the phosphor dots, otherwise a blue beam could technically hit a green phosphor dot. And how far away from the phosphor dots typically is the shadow mask. Would I be correct if it were on the order of millimeters or fractions thereof? Keep up the great work and thanks!

  5. 7:35 I didn't understand that. And this is even harder to understand: 8:05 how exactly does 2x rgb appear next to each other?

  6. Thanks to this videos I was able to answer a trivia question on what pixel is an abbreviation for. Thank you for your informative videos

  7. This video taught me what subpixels are for the longest time after watching speedruns where many people (jokingly or seriously) blamed subpixels for parts of their runs failing, and I had no idea what that meant until now.

  8. Wish I saw this video a year ago when it was fresh. How did CRT monitors overcome this limitation? Higher refresh rates ~85hz and much higher resolutions. Was the beam just a lot faster and smaller mask holes?

  9. The poster of Figment in the background at 2:17 brings me back to my childhood. Figment was my favorite Disney creation and holy shit, I never thought I'd see him in a video about tech.

  10. I still think they are pixels. Maybe they weren't intended to be but the are effectively limiting the detail. When I was a kid I would look out the screen door at a certain distance and say oh look pixels!!! Granted this is only true at a certain distance, but each hole in the screen became and effective pixel. I know the shadow mask is only there to produce color but I still see them as pixels. I mean you showed how having a limited number of the phosphors decreases the detail in certain cases even if it's still 480 lines. It is true though that a black and white tv has no pixels and just lines.

  11. I was looking at the definition of "pixel" on Wikipedia, and based on what you said and what I read on there, the "pixels" of a CRT display would be each line drawn, regardless of the shadowmask

  12. Much of this topic is just semantics.

    The physical arrangement of phosphor cells in the thumbnail aren't pixels; that's true. But there's still a meaningful definition of "pixel" for most color CRTs.

    The only meaningful distinction between an image made of pixels and a true 'analog' image is whether the image is discretized in both dimensions.

    Even from the days of black and white TV, images have been discretized in the vertical dimension with scanlines. That just leaves the horizontal.

    As seen in the video, most color CRTs separate the colors in the horizontal dimension. With vertical discretization built into the geometry of scanlines, and horizontal discretization built into the geometry of shadowmasks, we had two-dimensional discretization built into color displays right from the start.

    Therefore there's a meaningful definition of "pixel" as the smallest supported resolution of two-dimensionally discretized transmission of a particular color with a particular brightness.

    True enough, such pixels don't directly correspond to the shadowmask cells of the thumbnail. But contrary to the implication of the video, there is a definable pixel resolution of such displays.

  13. we should coin the term "display element" for all the people still arguing that the phosphor dots are pixels (picture elements).

  14. Read of the definition of the word "Pixel", it will tell you all you need to know as to why this video is wrong.
    Coming along years after the word was in use (as far back as the early 1960's to simply mean "picture element") and
    clouding the issue by conflating it with how the element was created does a disservice to the viewer.
    A picture element is still a picture element no matter how it is created , just as, a picture is still a picture regardless of it being painted, sketched, projected etc…
    What other words will you be retroactively redefining as technology evolves?
    Once we are all using quantum computing, years from now, I look forward to viewing your These Are Not Computers: video…

  15. Amazing video! The physical demonstrations you do paired with the metaphors behind it make it impossible not to understand the phenomena you're trying to describe!

  16. Another huge difference, that wasn't covered (or maybe it was mentioned in the comments somewhere already?). A pixel by definition has a single colour and a single brightness. A phosphor dot can have different levels of brightness across its entire area. Your tiny 5inch CRT actually illustrated this: I can see some rectangular phosphor dots that have a different brightness at the top versus the bottom. This is actually key! The CRT output STILL exhibits the continuous analogue brightness information even despite the apparent discretisation imposed by the shadowmask.

  17. Back when I was a wee bairn, I loved magnets. Playing with magnets near a CRT wasn't a good idea, though. And I'm pretty sure it helps demonstrate the Phosphors are not Pixels phenomenon: The image was only slightly distorted, but the colour was catastrophically altered, because the magnetic field caused the electron beams to swerve from their target phosphors after the mask.

  18. I was confused about this until I looked it up and saw it in writing. you were saying "addressed" with the connotation of a physical location determined by a number rather than "addressed" in the sense of interacted with directly. I misunderstood because I mentally pronounce the word as "AD-dressed" when referring to the first definition, and "a-Dressed" (the way you pronounce it) when referring to the second definition.

  19. Great description of how this stuff works, taking something fairly complicated like this and explaining it in a way everyone can understand can be tricky but you nailed it. You just got yourself a new subscriber, time to go binge watch some of of your videos!

  20. That’s a fair enough explanation. In most countries, using 625 lines, the analogue picture equated to a little more than 600 lines, and that handled 800 x 600 pixel computer data (converted to analogue) quite well. The US system was more compatible with converted 640 x 480 pixel data. The other notable exception was the French 819 line analogue TV standard, giving about 800 lines, but with poorer horizontal definition within similar analogue bandwidth.

    You didn't point out the fact that the electron beamwidth is significantly bigger than a colour triad. A bright beam means even bigger beam diameter, thus spreading over even more holes, or slots, in the shadow mask. Maybe you didn’t mention it in order to keep things simple, but you can see that the beam covers several phosphor triads, quite clearly, in some of your close-up shots.

    You could also have mentioned the fact that no two analogue CRT television displays show exactly the same image, because of alignment differences and distortions. Further proof that pixels are not being displayed.

    Incidentally, congratulations on finding both monochrome and colour analogue TV receivers which still work, years after they became obsolete. I haven’t seen a working monochrome receiver for almost 20 years.

  21. Lol I love how he will make multiple VERY DETAILED videos about the same thing just to clarify his point and educate people

  22. So… color CRTs do have pixels. Just because there is no digital logic involved in dividing the original analog single into discrete "color dots" doesn't mean that it isn't converted into them before being displayed. Unlike a modern display, the brightness is still analog, but discrete brightness isn't part of the definition of pixel anyways(and if you really want to split hairs, it is analog in modern screens as well).

    In fact, the color masking method used is almost exactly the same as modern LCDs. The main difference is that, in a modern screen, the mask is active and the light source is passive.

  23. I'll be darn. I knew about the red, green, and blue masks of CRT televisions (I still have one). (0:40) However, I didn't know that on current LCD televisions each sub-pixel was further divided into sub-sub-pixels.

  24. I would never go back to a bulky CRT TV for my entertainment, but strangely I think it's much more interesting and inventive how those old analog technologies worked compared to modern TV panels.

  25. Parts of the text didn't show because how far apart the green dots were. So… If there were more, and they were closer together…. ?

  26. both the CRT televisions I've owned in the last 15 years have a shadow mask 'resolution' of 480×480.
    Although there is a half cell offset each line so it never forms a clean grid.

    Still interesting to contemplate the implications though.
    Also if you observe an old console that uses the '240p' hack, you note that many of the cells are only half-lit, as only one field is ever active, and every other 'pixel' the scanning pattern doesn't line up with the grid.

    The true resolution limits of a CRT are more to do with the ability to focus the electron beam.
    The CRT monitors I had could officially do 1600×1200, but you could also coax one into displaying a 1920×1080 signal, however the result was a little bit on the blurry side…

  27. From the earlier videos I had assumed shadow maps were a bit more complicated than they were, but this really cleared it up! Also, as I watched this I was thinking about other ways you could explain it, and you pretty much demonstrated exactly that right after I thought it.

  28. I think it would help if you found one of those late 80s early 90s-ish TVs where the pixels/not pixels aren’t divided. They’re just sets of three lines going down the screen. I had an argument with someone about this exact thing 8 years ago. The argument went on for so long I eventually just agreed with him to shut him up.

  29. You're trying to say the "image" is the light that's projected before it hits the mask, and not the light that's emitted from the front of the screen. No one would ever be inclined to agree. The "image" most people refer to is the one on the screen. It doesn't matter how the "picture elements" are created, they are still elements of the picture. By the way, modern TVs still use a single source of light modified by a filter to create smaller parts of something bigger, so any way you look at it, what you are referring to as being pixels and not pixels are all fundamentally the same. That means they are all in fact pixels.

  30. Was upgrading/altering shadow-masks a thing? Wouldn't a finer shadowmask just straight up upgrade any given TVs colour-resolution? And were other shapes than circles, lines and squeres experienced with? Im sure there has to be other shapes that produce a complete grip with three lightsources, and one could even mesh up groups of different holes by increasing the distance between lightsources, producing a high colour-resolution picture with smearing of some sort.

  31. @5:28 Not sure if its how you processed this, or if its a simulation of snow. But in full screen I CAN see regularity vertically. During playback and when I pause during the snow I can see distinct, evenly spaced, regularly repeating vertical slices. And on some frames I can catch horizontal slices. YouTube compression madness messin' with your example?

  32. 2:12 HALT!!! CEASE ALL ACTION THIS INSTANT, STOP!! I would like to ask a question. I see a picture that's crammed to the right of the screen. Is that a picture of Spyro as a god damn chef? If it is, then I don't know what I'll do.

  33. is the colorburst carrier really QAM (quadrature amplitude modulation)? i always thought of it as PSK (phase shift keying). but, 30 years ago when i was studying the circuit diagrams of my heathkit TV, the color demod board was always the only board I had trouble understanding, and never completely figured it out.

  34. Pixel is just a term that stems from computer graphics (Think graphics designers started calling them Pic Cells first = Picture Cells.). Afaik they already started used the term way back in the 80s when CRT screens were the only available screens. I guess the term was already so ingrained when flat panel displays started appearing that they started using the same term to describe the individual cells in LCD panels. According to various pages the term Pixel was first used all the way back in 1965.

  35. A close up of a color TV signal being shifted left and right on a monitor with a horizontal position control would have soundly driven your point home.

  36. Great video and truly excellent explanation…, but it's "grid structure similar to," not "similar grid structure to." Also, all photons go through all holes. Weird, right?!

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