How Was Video Invented?

The film is a very simple technology. It simply involves taking a two-dimensional image, focusing it on two-dimensional film, and there you have a photo. But

video

, and by this I mean electronic moving images, has a very different history with many changes that have really transformed the way it works. This

video

was sponsored by B&H Photo, which is quite appropriate because that's where I get a lot of my equipment to make these videos. So I'll tell you more about them later, but now we're going to San Francisco. I'm meeting with a guy who knows a lot about old video equipment and has some he'll show me. - Richard, nice to meet you. - Nice to meet you Derek.

Enters. Welcome to the world of LabGuy. - What a good place you have here. - Thank you. - The fundamental problem of video is to take this two-dimensional light image and convert it into a one-dimensional electrical signal. So how do you do that? Well, the solution actually comes from the first fax machine, believe it or not, it was

invented

in 1843 by Alexander Bain. Now he was a watchmaker. His invention involved a transmitter and a receiver, each of which had a pendulum, and those pendulums were synchronized. So what would happen is, on the transmitter, there would be a sheet of metal on which something would be written or drawn using a non-conductive ink. - So a finger on the transmitter, an electric finger, caressed the paper and where there was iron it conducted, and that conductive signal was sent to the other end, which was applied to the paper with a darkening chemical. when electricity flowed through it and it would reproduce a very precise image of the handwritten note he just wrote. -Until now, Alexander Bain only transmitted static images, but some call him the true father of television, because he

invented

scanning.

This idea of ​​moving back and forth through an image, dividing it into lines. But if you really want to get moving images, you need to be able to scan much faster. So we have to jump to 1884, and a 23-year-old German university student named Paul Nipkow. He patented what is called a Nipkow disk, which is basically a large disk with a spiral of holes. - The internal holes do the scanning, and if I go fast enough you can see the scan. - You would put a light behind this Nipkow disc and then you would have a point of light that would scan the subject, says one person.

And then there would be light reflected off that person that would be picked up by some light sensors. That would create an electrical signal that could be transmitted remotely to a receiver. Now, at the receiver, you use that electrical signal to modulate the brightness of a light source, and then in front of it you place a synchronized Nipkow disk, and so the result is a recreation of the transmitter image. - So it was barely at the limits of the ability to make a viewable image, and in fact it was broadcast for a couple of years in Britain, and in the United States and other countries there were experimental broadcasts using this technique. - This is possibly the first image broadcast on television.

It was broadcast for a few hours a day for several years and was used by engineers to conduct experiments and try to improve the quality of the broadcast. -What he showed was that that was not the way to do it. - So, in 1939, mechanical television was practically eliminated and was replaced by an all-electric television. ♫ Specifically the cathode ray tube. This is a glass vacuum tube with an electron gun on the back. And the electron gun would fire a beam of electrons at the screen, where it was coated with a chemical substance that produced light when hit by electrons and was called a phosphor.

And using magnetic fields, this beam was scanned across the screen from top to bottom, left to right, and the brightness of the beam was varied by varying the voltage on a control electrode, essentially determining how many electrons would be sent. on that beam at any instant to hit the screen. So if you send out a lot of electrons, you get a bright spot; if not, you get a dark spot, and that way you can produce a nice black and white image. And if you're wondering about color television, well, there were several dead ends on the road to the red, green, and blue pixel system that became the standard.

Like this TV with a rotating color wheel. - I named the project Goldmark I after Dr. Goldmark. The TV part is a standard black and white picture tube. - It displayed 24 frames per second, but each frame required six scans: blue-green-red, blue-green-red. It worked great, but was not compatible with black and white TVs. And this is a mini triniscope, named for its three cathode ray tubes, one for each color. And their images were combined with prisms. - The disadvantage of a tri-scope monitor is that for every inch you add diagonally to your screen, the volume of the case increases by the power of something like three and a half.

They get huge quickly. - So the ultimate solution was to have red, green and blue phosphors for each pixel, and three electron guns to determine their relative brightness. - Now, the number of lines that these electron beams draw across the screen is, in theory, 525 every thirtieth of a second. But this is achieved by scanning every other line every sixtieth of a second, so it actually takes two scans to make a frame. This is called interlacing. And what you'll notice when watching this is that most of the time you're looking at a blank screen. The illusion of an image in continuous motion is possible thanks to our persistence of vision, that is, we do not stop seeing something instantly after light stops entering our eyes. - So, initially I thought this wouldn't be very difficult to film.

I mean, one-thirtieth of a second or one-sixtieth of a second, that's not terribly fast. But if you think about it, 262 and 1/2 lines are drawn every sixtieth of a second, that's 15,750 lines drawn per second. That's fast, so if you want to be able to see the lines being drawn, you need to shoot at over 15,000 frames per second - much faster, actually - to be able to see this clearly. and that's why I'm using the Phantom v2512. That is the beast that is allowing me to produce these images. Now the actual resolution of these TVs turned out to be around 480 lines, so when you select 480p on YouTube, that's why this is an option.

And I think it's worth noting that the "tube" on "YouTube" is this, a cathode ray tube. So, in the days before light-sensitive chips like the ones we all use in our cameras today, how was the image actually created for display on a television? Well, there were many vacuum tube designs. One of the most common was the orthicon picture tube, sometimes called Emmy for short. In fact, that's where the name the Emmys comes from. So the way it would work is to use the camera lens to focus an image onto the front of the orthicon image tube, and that was coated with a photoelectric substance, so it would release electrons in proportion to the light hitting them. .

Now those electrons were collimated by magnetic fields and sent directly back. Basically, an electronic version of the image was sent directly to a target, which was a very, very thin plate of glass. And of course, when there are more electrons, it creates a more negative point on this target. From the back of the tube you would send a beam of electrons to scan the target. And so, as these electrons came in, the more negative the spot on the target, the more the beam would be reflected. And then that reflected beam was amplified in the tube and then used as a signal to essentially determine how bright that part of the image should be.

This is how television images were created and displayed for decades. But here's the crazy thing: there was no way to record them. I mean the purpose of video or the purpose of electronic images was really to convey something from one place to another. "Television" literally means "viewing at a distance." It is not about recording to play back later as was done with film. - What surprised me was realizing that video cameras existed a couple of decades before video tapes. - That's how it is. That was the era of live streaming, but this introduced some problems. For example, in North America, in the United States, many of the television shows were produced in New York and there was a coaxial cable that ran across the entire United States that could transmit programming to, say, Los Angeles.

But it was at the wrong time. I'm talking about a newscast broadcast from New York at 6:00 or 7:00 p.m. You couldn't just go live at 3:00 or 4:00 p.m. On the west coast. It just didn't make any sense, so you needed to delay it. So how did they do it? Well, the answer was to take a movie camera, point it at a television screen, and actually film the television screen. You would then quickly develop the film and bring it back three hours later to stream it live, scan it, and stream it as if it were live. - But now, when I take it to the television studio and put it on the telecine, the image does not look good.

The lines aren't lining up correctly, plus you're trying to put two sets of lines back together and they don't! - This became such a common method of doing business for television networks that by 1954 the television networks, to delay their programming, used more films than all the Hollywood movie studios combined. This is absurd, expensive and wasteful, so a different method was really needed. And that came in 1956 with the invention of the first functional video recorder. It was the size of a large desk and cost a fortune. It ran on two-inch magnetic tape with small video heads spinning at 14,000 RPM.

We're talking as fast as a jet engine. That's the kind of technology that was needed before video became what we know today, a method of recording and storing images, rather than simply transmitting vision from one place to another. But we've come a long way since then, miniaturizing tape support to VHS and Beta, and eventually to DV and mini DV, and now we're into solid state storage. And you know I've glossed over a lot of the story here, but now we're in a situation where video is better than film. You can see that in 2012, that was the turning point between people using film to shoot blockbuster movies and the shift to people using digital.

And what this has done for people like you and me is that it has made it possible to create really good images. And the question I have is, what effect does this have on a society? What could you do when people can share every part of their lives on video? ♫ This part of this video was sponsored by B&H Photo, literally one of my favorite stores in the world. They have the latest and greatest camera equipment, plus professional audio and lighting and computers - basically everything you could need to shoot high-quality video. And every time I'm in New York, I go visit the store.

The last time I was there I asked them for a gimbal, because I've been seeing all these comments saying that my videos were too shaky, so they recommended this one here, and I really loved it. It's so soft. I can hold it with one hand. It's pretty lightweight and it's been great and I think it's really improved the quality of my videos. And when I go back to Los Angeles, I still shop with them online, because there is no store like that in Los Angeles. In fact, this camera, the Sony a7R III, I highly recommend, I bought it for my wife for Christmas last Christmas and it was backordered, but you can sign up through their website to be notified when it's available. in stock, I made it and managed to have it in time for Christmas, so it's a really great shopping experience.

The people are very knowledgeable, it is a family store, it has everything you could want. I highly recommend you check out B&H Photo. I'll put a link in the description. And thanks to B&H for sponsoring this video. ♫