Speaker 1: Brought to you by the reinvented two thousand twelve camera.
Speaker 1: It's ready. Are you get in touch with technology with
Speaker 1: tech stuff from how stuff works dot com. Hi there, kids,
Speaker 1: and welcome to tech stuff. My name is Chris Pelette
Speaker 1: and I'm an editor at how stuff works dot com.
Speaker 1: Sitting directly opposite me, as usual, is senior writer Jonathan Strickland.
Speaker 1: Let me take your picture added to the mixture. There
Speaker 1: it is. I got you now, really nothing to it.
Speaker 1: Anyone can do it. It's easy. And we all know
Speaker 1: how today's podcast really lends itself to that quote. Yes,
Speaker 1: today we wanted to talk about high speed photography and
Speaker 1: slow motion. Both of these have to do with a
Speaker 1: changing film speeds and shutter speeds and all this kind
Speaker 1: of stuff. To really talk about how the stuff works,
Speaker 1: we have to go a little bit more basic. We
Speaker 1: have to actually talk about the principles behind photography and
Speaker 1: how a camera works. And before we really get into this,
Speaker 1: How stuff Works has dozens of great articles about photography,
Speaker 1: including articles about how high speed photography works and how
Speaker 1: burst photography works. Both of those were written by John Fuller.
Speaker 1: But we also have how cameras work, how photographic film works.
Speaker 1: So if you want to learn more than what you know,
Speaker 1: we're going to kind of cover the basics. But if
Speaker 1: you really want to know the true science and chemistry
Speaker 1: and physics behind how cameras work, I highly recommend you
Speaker 1: check out those articles because they will answer a lot
Speaker 1: more questions. We're gonna try and kind of cover the
Speaker 1: basics here. So so let's uh, let's talk about what
Speaker 1: a camera does. It's seemed kind of silly to say
Speaker 1: because we're most of us really familiar with cameras. And
Speaker 1: by the way, I should point out also that we're
Speaker 1: really focusing on film phil it was completely not on purpose. Um,
Speaker 1: we're talking about film cameras mainly in this podcast as
Speaker 1: opposed to digital. The two different methods. You know, you
Speaker 1: get the you get a result that's similar using these
Speaker 1: two methods. You know, you get an image of a
Speaker 1: moment in time in both ways, but the actual mechanics
Speaker 1: behind film versus digital are very different. So we're specifically
Speaker 1: looking at it's gonna say, focus again looking at film
Speaker 1: cameras because well, to to to try and cover both
Speaker 1: would require a like a podcast that's twice as long
Speaker 1: as what we normally do, and we only do that
Speaker 1: for Google Plus well, UH cameras in general though, UM
Speaker 1: and speaking of both film and digital, you're you're you're
Speaker 1: using a series of UM devices to capture that image. There.
Speaker 1: On both film and digital you of course you've got
Speaker 1: a lens um and there is UH, the principle behind
Speaker 1: it is to capture the image. On film, you're using
Speaker 1: a a piece of essentially plastic celluloid to that's treated
Speaker 1: with chemicals they captures that image, and in a digital
Speaker 1: camera use an image sensor. UM. But you know, and
Speaker 1: and there are some similarities of course. It It has
Speaker 1: to do with how fast the camera is firing UM
Speaker 1: and how much light you're letting in through the lens
Speaker 1: um and after that they do differ considerably. So with
Speaker 1: a with a film camera, you know, Chris was just
Speaker 1: talking about it a second ago. But what you know,
Speaker 1: the main the medium upon which you are capturing these
Speaker 1: images is film, and film is really just a strip
Speaker 1: of plastic that's been treated with UH, with chemicals that
Speaker 1: are photoreactive. Yes, that means that the chemicals will undergo
Speaker 1: some sort of change when exposed to light, so they
Speaker 1: turned into monsters. If you've listened to our solar If
Speaker 1: you listen to our Solar Panel episode, you know that
Speaker 1: we have discovered materials that react when light hits it.
Speaker 1: The photons from the light transfer energy to whatever that
Speaker 1: medium is and you get a reaction. In this case,
Speaker 1: the photons are able to change the chemical properties of
Speaker 1: the stuff that's on this film. And I really get
Speaker 1: into that would be diving deep into science. We do have,
Speaker 1: like I said, the article on how photo, how film
Speaker 1: photographic film works, and that explains it. But UM, to
Speaker 1: be honest, if I were to try and go into
Speaker 1: it right now, I'm sure I would mess it up
Speaker 1: because you know, my my chemistry is only goes so far.
Speaker 1: My chemistry food is weak chem But at any rate,
Speaker 1: what this this stuff is designed so that when light
Speaker 1: hits it, it has a chemical change. Then when you
Speaker 1: treat it with other chemicals, that's what allows you to
Speaker 1: create a negative image of whatever it was you were,
Speaker 1: whatever light hit it. So this is why when you
Speaker 1: have film, people say, you know, make sure you don't
Speaker 1: expose it to light before before or after you take
Speaker 1: a photo, because if you do, it's going to ruin
Speaker 1: the image, right because um, the film is going to
Speaker 1: record the light from the that that is coming to
Speaker 1: it through the lens. So of course, when you put
Speaker 1: the canister a film inside your camera and load your camera,
Speaker 1: you close the door which blocks off any light. Um.
Speaker 1: And then of course you have to advance the film
Speaker 1: after you've taken a photo. If you if you've ever
Speaker 1: exposed film more than once, double exposure, you get a
Speaker 1: really bizarre effect. Yeah. Yeah, And it can be very
Speaker 1: very cool if that's what you're going for. It can
Speaker 1: also be really frustrating if you were trying to capture
Speaker 1: one thing in particular and forgot to advance the film, right.
Speaker 1: And and we've even seen that double exposures go into
Speaker 1: uh the realm of people thinking that something supernatural roles
Speaker 1: going on, because you do get kind of a ghostly
Speaker 1: image if you double exposed film. Yeah. So there have
Speaker 1: been times where people have had just a double exposure,
Speaker 1: that's all it is, but because they didn't realize it
Speaker 1: was a double exposure, they think, Wow, I took this
Speaker 1: photo of my buddy Bob, and there's this ghostly face
Speaker 1: that's appearing over his left shoulder that's so creepy, and
Speaker 1: not forgetting that, oh before I took the photo of
Speaker 1: Bob I took a photo of Liz. It's just that
Speaker 1: Bob's photo was exposed over Liz's photo, and now Liz
Speaker 1: looks like she's a ghost. Actually, I thought it was
Speaker 1: because Bob worked at that leaky nuclear plants. Because we
Speaker 1: took all those photos over that Indian burial ground. That
Speaker 1: was a mistake we made anyway. Um uh. The the
Speaker 1: the idea here is that the camera gives you a
Speaker 1: very controlled way to expose that film to light. And
Speaker 1: the way this works is that first you've got the lens,
Speaker 1: and the lens is purpose is to direct light to
Speaker 1: the film, So the lens is allowing light to pass through.
Speaker 1: When light passes through a lens, that actually the speed
Speaker 1: of the light changes. You know, speed of light is
Speaker 1: a constant, but it's a constant that's based upon whatever
Speaker 1: the medium it is that it's traveling through. For example, air, Yeah, air,
Speaker 1: it's going to travel through it. Light travels through air
Speaker 1: much more quickly than it will a lens. And the
Speaker 1: curvature of the lens, the thickness of the lens, that's
Speaker 1: all going to make the light travel at at slightly
Speaker 1: different speeds. The point being that you focus all that
Speaker 1: this light onto a point so that it exposes just
Speaker 1: the right spot on the film. Now, behind that, you've
Speaker 1: also got a device called the aperture. Now the aperture
Speaker 1: is essentially a hole. It's a it's it's a disk
Speaker 1: that can expand or contract and allow more or less
Speaker 1: light to pass through the from the lens to the film.
Speaker 1: So it's it's a barrier between the lens and the film.
Speaker 1: And you adjust this in order to uh to really
Speaker 1: kind of tweak your photo settings, like with a with
Speaker 1: a manual camera, a manual single lens reflex camera or
Speaker 1: SLR manual SLR uh by the way, in case you're curious,
Speaker 1: for those of you who are only familiar with digital cameras,
Speaker 1: a manual single lens reflex camera is not electric at all.
Speaker 1: It's it uses chemicals and it uses mechanical little gears
Speaker 1: and things, but there's there are no electric components necessarily
Speaker 1: in a true manual single lens reflex or at least
Speaker 1: you don't have to have any electronic I think that's
Speaker 1: so in other words, it's kind of interesting because we
Speaker 1: we take it for granted now with digital cameras. Right,
Speaker 1: digital cameras, you have lots of electronic components, but with
Speaker 1: a a an old manual single lens reflex, you're just
Speaker 1: you're just turning little dials, which is advancing the film.
Speaker 1: You might turn a little crank to rewind film, but
Speaker 1: there's nothing necessarily electronic in it. Um. Of course, there
Speaker 1: are hybrids that as well, But anyway, this the aperture
Speaker 1: helps you determine how much light can enter through the lens.
Speaker 1: And then you have something else called the shutter, and
Speaker 1: the shutter determines how long the film is exposed to
Speaker 1: that light. So if you were to take a photograph
Speaker 1: with a shutter speed that is a you know, it
Speaker 1: allows the shutter to be open longer, then your photo
Speaker 1: is going to be a little more blurry, unless the
Speaker 1: subject of your photo is incredibly still. So if the
Speaker 1: camera is still and the subject is still, and you've
Speaker 1: got a decent amount of lighting, and the shutter is
Speaker 1: open longer, theoretically, as long as as long as the
Speaker 1: light's not too great, you will actually get a very
Speaker 1: clear image because it's it's really capturing that uh, that
Speaker 1: moment um. Now, if something is moving, then you're gonna
Speaker 1: get a blur. So if you've ever looked at some
Speaker 1: nighttime photography especially or like city scapes where you can
Speaker 1: see where traffic is moving through and it's like beautiful
Speaker 1: red streaks on one side of the road and white
Speaker 1: streaks on the other that you know, that's obviously the
Speaker 1: traffic where cars are coming and going. That's usually using
Speaker 1: a camera with a shutter speed where the shutters remaining
Speaker 1: open longer. Sometimes it can be as long as you know,
Speaker 1: minutes or or more, and that creates that streaking effect
Speaker 1: because all that light is hitting the camera over an
Speaker 1: extended time, so instead of seeing individual cars, you're seeing
Speaker 1: these streaks. Yeah, this this has basically it's a combination
Speaker 1: of things. It's a combination of the aperture setting that
Speaker 1: you're using to expose the film, uh, the shutter speed,
Speaker 1: and there are cameras that you can manually hold the
Speaker 1: shutter open uh as long as you want to. It's
Speaker 1: often better and creating the photos like Jonathan was just
Speaker 1: talking about, where you leave it open for minutes to
Speaker 1: have your camera on a tripod and use a cable release,
Speaker 1: you know, just so that you don't nudge the camera
Speaker 1: because otherwise you're going to uh jar the picture and
Speaker 1: distort things. So yeah, it also has to do with
Speaker 1: the speed of the film. And uh, it's funny because
Speaker 1: that's sort of a misnomer. You know, there aren't little
Speaker 1: canisters of film moving faster than others. It has to
Speaker 1: do with the chemical properties actually the film. UM. And
Speaker 1: again we're not going to get into the chemistry behind
Speaker 1: it so much. UM. But uh, you know, depending on
Speaker 1: the speed of the film, you would be able to
Speaker 1: capture uh photos in darker environments or lighter environments. UM. Also,
Speaker 1: the speed of the film has is depending on on
Speaker 1: this the type of photography you're doing. If you're trying
Speaker 1: to capture high or fast motion photography, you're gonna want
Speaker 1: something that you can expose um to light more frequently,
Speaker 1: like a higher speed film. UM. You know, you want
Speaker 1: something that's going to to just from a very brief
Speaker 1: exposure be able to capture an image. And and by exposure,
Speaker 1: we're talking about exposing to light. You know, just keep
Speaker 1: that in mind that that exposure has everything to do
Speaker 1: with the amount of light and the duration of light
Speaker 1: that hits that film. So a high speed film can
Speaker 1: capture an image with light hitting it for a shorter
Speaker 1: time frame. And we're talking fractions of a second. Here,
Speaker 1: you know, when we talk about a short time frame,
Speaker 1: we're talking really short. We're not talking like, oh, well,
Speaker 1: you know a woman thousand two one, now you would
Speaker 1: be able to take hundreds of photos in the mount
Speaker 1: of time. It took me to say that depending on
Speaker 1: the speed of the film and the shutter speed and
Speaker 1: all of this kind of stuff. So so high speed
Speaker 1: photography kind of leads us into this. High speed photography
Speaker 1: is all about trying to capture, uh an image of
Speaker 1: something that's moving at an incredible speed, something that that
Speaker 1: is moving so fast that to the naked eye it
Speaker 1: may be either a blur or perhaps even you know,
Speaker 1: practically invisible because it's going so quickly. But you want
Speaker 1: to be able to capture that moment in time so
Speaker 1: that you can see a very distinct image. Well, this
Speaker 1: is a challenge. You have to figure out how are
Speaker 1: you going to do that, and a couple of different ways.
Speaker 1: Perhaps I hesitate to say the easiest way, but perhaps
Speaker 1: the simplest way is to set up your camera in
Speaker 1: a perfectly dark room and you just leave the shutter open.
Speaker 1: Because remember, even though the shutters open that film, if
Speaker 1: there's no light, the film is not being exposed. So
Speaker 1: you've got this film that's just sitting there. Nothing's happening
Speaker 1: to it. It's not reacting chemically at all because there's
Speaker 1: no light coming into the camera. You set up whatever
Speaker 1: the thing is you want to take a photo of,
Speaker 1: and then you have it timed out so that the
Speaker 1: instant that thing happens, there is a flash of light
Speaker 1: that is up and down in a fraction of us
Speaker 1: can and just that fraction of a second is going
Speaker 1: to be long enough for the light to go through
Speaker 1: the camera and uh and to expose the film. Then
Speaker 1: you could advance the frame and do it again. Now,
Speaker 1: this is a very slow, painstaking process, and it requires
Speaker 1: an incredible amount of timing, and there are a lot
Speaker 1: of different ways of setting up a shot so that
Speaker 1: the uh, the the light will trigger at the right moment.
Speaker 1: Some of them are acoustically triggered so that there's a
Speaker 1: noise and that noise causes the light to flash, which
Speaker 1: automatically exposes the film in the camera. You don't have
Speaker 1: to do anything to the camera at that point, right,
Speaker 1: You're not pushing a button because the camera shutter is
Speaker 1: already open. It's only after the light is flashed that
Speaker 1: you have to advance the film so that you can
Speaker 1: take another photo. Otherwise you're going to have a double exposure,
Speaker 1: high speed double exposure on this this film, which I
Speaker 1: think would look really weird. Um. So that's one way
Speaker 1: you can do it. But of course, if you want
Speaker 1: to take a high speed photo of something nature, for example,
Speaker 1: the the an example that a lot of people use
Speaker 1: as a hummingbird, because a hummingbird can beat its wings
Speaker 1: so quickly that with most cameras, if you took a
Speaker 1: picture of a hummingbird with a standard camera, it's gonna
Speaker 1: look like a bird with two blurs next to it, right,
Speaker 1: you won't be able to see the wings. Um. But
Speaker 1: if you use a high speed camera where it's able
Speaker 1: to move the shutter at a really fast rate, and
Speaker 1: you have a pretty well lit environment, then you might
Speaker 1: be able to capture an image of a hummingbird where
Speaker 1: you've got its wings perhaps in the upper down position,
Speaker 1: and you can get a really clear look at that bird.
Speaker 1: But it does require that you have a camera that
Speaker 1: can move that shutter speed at a really really fast rate,
Speaker 1: and that you have a high speed film that's capable
Speaker 1: of taking light for a incredibly brief exposure time and
Speaker 1: convert that into an image. Yeah. You know, UM, if
Speaker 1: you're a text a listener normally UM that we like
Speaker 1: to get into the history of things. And I wouldn't
Speaker 1: necessarily have have thought of high speed photography is I
Speaker 1: would have thought it was a more modern UM, something
Speaker 1: that was more modern phenomenon. But really the history of
Speaker 1: high speed photography goes back just about as long as
Speaker 1: the history of photography itself. UM. The first example that
Speaker 1: I I read about UM from a a uh AN
Speaker 1: article by Lincoln l Endelman, which was William Henry Fox
Speaker 1: Talbot's uh trial where he basically exposed a piece of
Speaker 1: the London Times newspaper that was on a wheel that
Speaker 1: he attached it to, and he was using a wet
Speaker 1: plate camera, which is basically a piece of glass that's
Speaker 1: treated with chemicals rather than a film camera. Interesting. I
Speaker 1: had never heard of that before there was one, and
Speaker 1: heard of the camera obscura, which, by the way, you
Speaker 1: can actually build one of those yourself if you or
Speaker 1: wanted to, But I've never heard of the wet plate camera.
Speaker 1: That's interesting. He uh and for a flash he was
Speaker 1: using laden jars elimination from laden jars. This is like
Speaker 1: the coolest camera ever. Yes, and cumbersome because you know,
Speaker 1: you don't really take this thing out to go take
Speaker 1: shots at the family on vacation. I'm out to the
Speaker 1: high school football game. Let me carry my laden jars
Speaker 1: and wet played caral with me. But but I need
Speaker 1: the team's help setting this up. But he didn't manage
Speaker 1: to get a readable photo of the newspaper at the
Speaker 1: shutter speed of one of second unexposure speed. Let's say
Speaker 1: that actually used. But you also probably remember Edward Mindbridge.
Speaker 1: I remember the name. Yes, yes, he had a famous
Speaker 1: experiment where um, he had set up a series of
Speaker 1: cameras too, because there was a challenge. Um, you may
Speaker 1: have heard of this guy, uh um Laden, I'm sorry, yeah,
Speaker 1: I'm sorry. He may have heard of this guy at
Speaker 1: Leland Stanford. He was the governor of California and he
Speaker 1: was that that was the challenge was does a horse
Speaker 1: pick up all four of its feet when it's running?
Speaker 1: And he was the one my bridge and a lot
Speaker 1: of people have seen this, uh seen this series of
Speaker 1: photos where they proved that the horse was picking up
Speaker 1: all four of its feet because he had a series
Speaker 1: of cameras and that the horse was tripping it as
Speaker 1: it ran by, and so each camera took photos a
Speaker 1: different a different way of doing it, but they captured
Speaker 1: a series of still photos because as the horse was
Speaker 1: running by, it took you know, each camera in turn
Speaker 1: took a still photo, and when you put them all together,
Speaker 1: you get essentially slow motion of this horse running. Yeah,
Speaker 1: and yes it does pick up all of its feet
Speaker 1: when we'll get it, and we'll get into that in
Speaker 1: a little bit, because of course the photography does lead
Speaker 1: into cinematography. But before we do, I, before we jump
Speaker 1: into that, I just wanted to mention one other kind
Speaker 1: because I did mention burst photography when we were for
Speaker 1: introducing this podcast, and that that John Fuller, Editor Extraordinaire
Speaker 1: UH wrote the article on how burst photography works. First,
Speaker 1: photography works on a similar principle of high speed photography. Now,
Speaker 1: with high speed photography, you may be talking about taking
Speaker 1: a single image and then setting up and taking another
Speaker 1: single image, right right, That's like I'm pointing, I'm pointing
Speaker 1: my camera at a hummingbird and I take one photo. Right.
Speaker 1: The point of the high speed photography here is to
Speaker 1: capture a very accurate still. Yeah, yeah, something that's going
Speaker 1: to be. It's really used a lot in things like sports,
Speaker 1: you know, trying to catchure, capture that dramatic moment where
Speaker 1: the quarterback is releasing the hail Mary pass. I'm saying
Speaker 1: that right, right, because I don't know anything about football
Speaker 1: or you know, the people who absolutely positively have to
Speaker 1: have that shot of the water balloon after the balloon
Speaker 1: is broken and the water is still in the balloon shape,
Speaker 1: but for the apple with the bullet through it. But
Speaker 1: clearly this sort of that has to happen, this sort
Speaker 1: of this sort of event is of course really hard
Speaker 1: to capture on film, not just because of the nature
Speaker 1: of the mechanics where you know, you've got to have
Speaker 1: a camera with that proper shutter speed and film with
Speaker 1: that proper um photochemical reaction speed. You also have to
Speaker 1: have insane timing, and even by setting up an automated
Speaker 1: system where everything's going to happen automatically, you know, as
Speaker 1: soon as the event happens, it triggers the camera. Even
Speaker 1: that is really difficult to do. So perhaps what if
Speaker 1: you could have a camera that could shoot a series
Speaker 1: of photos in a very short amount of time using
Speaker 1: that same kind of principle. Well, that's what burst photography
Speaker 1: is all about. These are cameras that have not just
Speaker 1: the really fast shutter speed and not just the special
Speaker 1: film that's going to to react quickly to a very
Speaker 1: brief exposure, but also the ability to advance film rapidly
Speaker 1: as you're taking photos. So with a burst photography camera,
Speaker 1: it's pulling the film through very quickly and the shutter
Speaker 1: is opening and closing, causing multiple exposures, but you're not
Speaker 1: not a double exposure because you're you know, the films
Speaker 1: being pulled through as you're as you're doing this so
Speaker 1: that you can take a series of photos in a
Speaker 1: brief amount of time, so like in a second or two,
Speaker 1: you might take dozens or more photos. And this way, Uh,
Speaker 1: the nice thing about this is that you can point
Speaker 1: your camera at whatever the event is and just start
Speaker 1: shooting photos until you're out of film and you have
Speaker 1: a better chance of capturing that iconic moment you're after
Speaker 1: as a photographer. Yeah, this is uh, this is one
Speaker 1: of those times if if you haven't really done a
Speaker 1: lot of work with people who are professional photographers, and
Speaker 1: you might be going Last time I bought film, I
Speaker 1: only had twenty four exposures on a roll. You can buy,
Speaker 1: you know, if if you are interested in doing this, Uh,
Speaker 1: you can buy whole magazines of film and you know,
Speaker 1: attach them to the back of your camera where you
Speaker 1: have a very very long roll. Or you can of
Speaker 1: course make your own, uh, if you're so inclined and
Speaker 1: are good in the dark. I used to have to
Speaker 1: actually I was a newspaper report for a couple of years,
Speaker 1: and um, you know, we'd have a big roll of
Speaker 1: film and we'd load the magazines are are the cartridges ourselves.
Speaker 1: And after a while you get pretty practiced at it.
Speaker 1: But the first few times, uh, I wasted some film. Um,
Speaker 1: but yeah, I mean so so this is sort of
Speaker 1: one of those times when digital cameras sort of have
Speaker 1: an advantage because now that we have bigger memory cards
Speaker 1: and better digital photography. Um, the digital cameras are are
Speaker 1: so much easier and more cost effective uh than than
Speaker 1: film cameras in this regard. But the burst photography is amazing,
Speaker 1: especially if you are you know, it allows you to
Speaker 1: set up and have a much better shot at getting
Speaker 1: your shot than than just just clicking and hoping that
Speaker 1: you got it. Yeah. Yeah, Well this kind of leads us,
Speaker 1: like I said, into cinematography, using film to capture images
Speaker 1: in motion where you are going to play it back
Speaker 1: so that you have the illusion of motions. So remember
Speaker 1: film as in like I'm going to the movies to
Speaker 1: watch a film is the the illusion of movement. And
Speaker 1: it works because we capture lots of images and then
Speaker 1: we put them in order and we, uh, we expose
Speaker 1: our eyeballs to those images very in rapid succession, and
Speaker 1: that creates the illusion of movement. So uh, the typical
Speaker 1: film projector will play back film at a rate of
Speaker 1: around twenty four frames per second, which means that every
Speaker 1: second that passes, you're looking at twenty four images. Twenty
Speaker 1: four photographs essentially, is what that is. So you're looking
Speaker 1: at twenty four photographs in a row per second. Because
Speaker 1: of that, it sort of gives this, It gives this
Speaker 1: the illusion of the things that you're looking at are
Speaker 1: really moving. It's not that you're looking at instances that
Speaker 1: are put together. It's like it feels like a flowing
Speaker 1: motion that has no no real interruption to it. I
Speaker 1: think it's interesting to note too that when you're you're
Speaker 1: saying twenty four frames per second. That's each frame is
Speaker 1: a second. That seems pretty fast. But in my research
Speaker 1: on high speed photography, I saw mentions of one eight
Speaker 1: of a second. Um. Of course that would take a
Speaker 1: whole lot of film. Yeah, but you know, it's it's
Speaker 1: interesting to note that a second is reasonable enough to
Speaker 1: give us an idea of motion and to create that
Speaker 1: illusion for us. So, if you have a projector that's
Speaker 1: going to play film back at a steady rate, so
Speaker 1: let's let's go with the twenty four frames per second.
Speaker 1: But you have a camera that can take that can
Speaker 1: actually exp those film at a variable rate. That's where
Speaker 1: you can start playing with the slow motion or fast
Speaker 1: sped up motion on films. So if you've ever watched
Speaker 1: an old movie where for comic effect, usually characters start
Speaker 1: moving around really really quickly, you know, like there's a
Speaker 1: chase scene and suddenly everyone's running at a speed that
Speaker 1: doesn't really look natural. Yankety sacks may very well be
Speaker 1: playing they did, and that's none of that, um, before
Speaker 1: I get sued and uh, anyway, yeah, so this this
Speaker 1: is playing with taking more images per second and then
Speaker 1: playing it back at a steady speed. Um. Now, in
Speaker 1: the old days, the good old days of filmmaking. Those
Speaker 1: days you had cameras that were hand cranked, which meant
Speaker 1: that you had a camera man or camera woman really
Speaker 1: camera person um turning a crank that was squirrels possibly
Speaker 1: turning a crank and hopefully a fairly consistent speed for
Speaker 1: normal filming to advance the film through the camera as
Speaker 1: it's being exposed to light. And the idea of being
Speaker 1: that you want to turn the camera at a good
Speaker 1: rate so that when you're projecting it back through the
Speaker 1: projector it's a steady, smooth experience right when you are dB.
Speaker 1: So yeah, so this this camera is not automated, it's
Speaker 1: it's it's manpowered, and people are known to be you know, imperfect. Yeah,
Speaker 1: not terribly consistent sometimes. Um so, yeah, if you turn
Speaker 1: the crank faster than normal, you'd be exposing more film
Speaker 1: in the same amount of time than you would if
Speaker 1: you were going at your normal rate, which and when
Speaker 1: you're playing it back, remember you're playing it back at
Speaker 1: a h at a fixed rate. So if you've captured
Speaker 1: more images in that amount of time then normal, then
Speaker 1: you get the effect of slow motion, right because while
Speaker 1: you've while you've captured maybe say, uh, you know, forty
Speaker 1: eight images and then uh, you know, so you're looking
Speaker 1: at forty eight images over the space of a of
Speaker 1: two seconds. Uh. If it were played back at normal speed,
Speaker 1: now you're looking at it at one second while everything
Speaker 1: starts to slow down. That could be distracting. Yeah, so
Speaker 1: this is a that's over cranking. Yes, it's when you're
Speaker 1: cranking the camera faster than the projection playback speed. And
Speaker 1: there's also under cranking, where you turn the crank slower
Speaker 1: than the projection speed. This causes a sort of the
Speaker 1: herky jerky fast motion stuff that you see, especially in
Speaker 1: older films, where people start to are moving faster than
Speaker 1: they normally could, and often it looks a little jumpy
Speaker 1: because you're missing information. Right, the the the more amount
Speaker 1: of time you have between when two images are taken
Speaker 1: for something that's in motion, the less natural it's going
Speaker 1: to look when when you're playing it back. Right. Because
Speaker 1: so if I took a picture of Chris right now,
Speaker 1: and then three seconds later took another picture, and three
Speaker 1: seconds later took another picture, until I had, you know,
Speaker 1: two photos, and I played them back at an at
Speaker 1: a regular speed, uh, where it would look really really jerky,
Speaker 1: you know, it wouldn't look natural at all and jerky,
Speaker 1: not just because of the subject matter, but bump bump.
Speaker 1: So it's only because I've been dried and cured. Right.
Speaker 1: So you may have heard of the term of speed ramping.
Speaker 1: Speed ramping is when you in the good old days,
Speaker 1: it was done by accident, but today we do it
Speaker 1: on purpose. Speed ramping is when you change the capture
Speaker 1: rate of uh the film or video during a shoot,
Speaker 1: and this is where you get those weird effects where
Speaker 1: like it's often done in action sequences. For example, let's
Speaker 1: say it's a fist fight between two characters and it
Speaker 1: starts out normal, and one character starts to throw a punch,
Speaker 1: and just as the characters throwing a punch, it switches
Speaker 1: so it goes into slow motion, and then just as
Speaker 1: the punch makes contact with the other person, it speeds
Speaker 1: up again and it changes, uh the the capture rate,
Speaker 1: but the playback rate remains constant. That's what we call
Speaker 1: speed ramping. And there's certain directors who are infamous for
Speaker 1: speed ramping. Um just you know, if you ever have
Speaker 1: seen the movie three hundred or Watchmen, you know one
Speaker 1: of the ones I'm talking about use a speed ramping
Speaker 1: so much that it's distracting at times for some people.
Speaker 1: Other people love it. I I personally think a little
Speaker 1: goes a long way. I'm sorry anyway, that they're all
Speaker 1: based on the same principle, the fact that if you
Speaker 1: keep the playback rate steady and you change the capture rate,
Speaker 1: you can you can make film appear to move slower
Speaker 1: or faster. Um. Now, you could also play with the
Speaker 1: playback rate. If you kept the capture rate the same
Speaker 1: and you change the playback you would get the same effect,
Speaker 1: right you would. You would either try and display more
Speaker 1: images per second or fewer images per second than normal,
Speaker 1: and you could get the same. Fact. This is a
Speaker 1: lot easier to do in video than it isn't film. Sure, sure,
Speaker 1: but it's funny to note again that like so many
Speaker 1: other things in photography, that the key to slow motion
Speaker 1: is high speed photography. Um. To to really get an
Speaker 1: idea of what's happening and slow it down, you have
Speaker 1: to capture many images so that you can you can
Speaker 1: go from image to image at a slower rate and
Speaker 1: really get a good idea of of the motion and
Speaker 1: how things are transpiring. Uh in that image. Yeah, yeah,
Speaker 1: if you if you take an uh a video of
Speaker 1: something or a film of something, and it's at eight
Speaker 1: thousand frames per second, and you play it back on
Speaker 1: a twenty four frames per second projector, it's going to
Speaker 1: take you a long time to get through. Like even
Speaker 1: if you only shot for maybe five seconds, you know
Speaker 1: that's gonna take you a long time to get through
Speaker 1: those five seconds when you're playing it back at a
Speaker 1: rate of twenty four frames per seconds. So then you
Speaker 1: get this incredible slow motion effect where at times it
Speaker 1: may look like nothing is even moving because everything is.
Speaker 1: You know, you're capturing such tiny moments of time that
Speaker 1: it's hard for us to detect changes until they are
Speaker 1: dramatic changes. And this is where you can't. You can
Speaker 1: see some of those really cool effects where like Chris
Speaker 1: was saying, the water balloon, where you pop the balloon
Speaker 1: and the water has retained the balloon shape for a
Speaker 1: couple of a couple of split seconds, like moments in time,
Speaker 1: and then you start to see it. You know, of course,
Speaker 1: fall uh that that's we've seen some really cool footage
Speaker 1: because of the this uh this technique, and you can
Speaker 1: too if you go to the house stuff works dot
Speaker 1: com site. We have a lot of clips from the
Speaker 1: Discovery show Time warp Um, which was really popular a
Speaker 1: couple of years ago because it showed extreme slow motion. Yeah,
Speaker 1: using amazing high definition slow motion cameras that are taking
Speaker 1: thousands of frames of footage per second and then playing
Speaker 1: it back at normal speed. Yeah, and it's just it's
Speaker 1: absolutely amazing. I can. I can watch them all the time,
Speaker 1: you know, even the ones I've seen before, you know,
Speaker 1: I can. I can go back and watch it just
Speaker 1: because it's so fascinating how how all that works. I
Speaker 1: love the ones where people get slapped and you just
Speaker 1: see the face deform slowly. Wow, that's what happens. Whenever
Speaker 1: I say anything to anyone that's insane. I'm I'm constantly can't. Yeah,
Speaker 1: my face is hurting. I got slapped just before this podcast.
Speaker 1: Actually yeah, but it was you that did it anyhow.
Speaker 1: I never said that it was necessarily caused by someone else.
Speaker 1: That's true, that's true. But yeah, I mean you can
Speaker 1: you can. You can see at right now. They're they're
Speaker 1: still up there. And I think when we post this
Speaker 1: will probably I'm pretty sure there's a playlist we can
Speaker 1: we can show people. Yeah. Um, yeah, that just it's
Speaker 1: just a lot of fun to do that. And it's
Speaker 1: a lot of fun to to fool around with high
Speaker 1: speed photography just as that, you know, just as somebody
Speaker 1: who is a hobbyist, um, to see what you can
Speaker 1: do with it. And now, granted, if you want to
Speaker 1: get like a really good high speed camera, this can
Speaker 1: be an expensive hobby. Yeah. I mean, if you're talking
Speaker 1: about the top of the line uh kind of set up,
Speaker 1: then you're you're looking at thousands of dollars. So it's
Speaker 1: not a cheap hobby necessarily, but it does really it's
Speaker 1: really cool now and then you know, if you're if
Speaker 1: you're really staging things too, um, yeah, of course, then
Speaker 1: you have got the whole staging costs and stuff. Yeah,
Speaker 1: and you're starting to talk about again because it is
Speaker 1: a matter of uh, the camera detecting the image and
Speaker 1: and getting synchronized with the the event that you're trying
Speaker 1: to photograph, and um, you know you have to buy
Speaker 1: the equipment to do that. We were talking about sound equipment.
Speaker 1: They are setups that require you know that that the
Speaker 1: sound will true cause the the camera to fire. And
Speaker 1: you know this is again you're having to buy more gear. Um.
Speaker 1: But it's it's it's fun if you can afford it.
Speaker 1: It's pretty pretty interesting stuff. So yeah, this wraps up
Speaker 1: at our discussion about high speed photography, slow motion cameras
Speaker 1: in general film. Uh stuff is really really interesting. In fact,
Speaker 1: it's so interesting to me that when I look at
Speaker 1: the complexity of these devices. I mean, the principle is
Speaker 1: pretty simple from a high concept point of view, but
Speaker 1: when I start looking at the ingenuity that was required
Speaker 1: to bring a camera into reality, Uh, I just it's
Speaker 1: phenomenal to me. Again, It's one of those things where
Speaker 1: we take it for granted now because they're everywhere. I mean,
Speaker 1: we have cameras incorporated into practically every mobile device you
Speaker 1: can think of, but the principles behind it, and it's
Speaker 1: just it's just phenomenal, amazing that we figured us out. Yeah,
Speaker 1: I mean think about we I mean, people way smarter
Speaker 1: than I am. Well, you think about how the difference
Speaker 1: in the early cameras that you know, degaro types and
Speaker 1: and the wet plate type devices versus the tiny little
Speaker 1: cameras in our smartphones, you know, shoes and everything else.
Speaker 1: I don't want any shoe cameras. Let's let's not do that. Okay, alright, alright,
Speaker 1: shoot people out there, don't put cameras in your shoes.
Speaker 1: How about diamonds on the soldier shoes? How about self
Speaker 1: lacing shoes? Hey, they just came out with those. Yeah,
Speaker 1: well all right. Anyway, we're gonna wrap this up. So guys,
Speaker 1: if you have any topics you would like us to
Speaker 1: talk about, please let us know. You can let us
Speaker 1: know through email. Our address is tech stuff at how
Speaker 1: stuff Works dot com, or you can drop us a
Speaker 1: line on Facebook or Twitter. Our handle there is text
Speaker 1: stuffed H s W. Chris and I will talk to
Speaker 1: you again really soon. Be sure to check out our
Speaker 1: new video PI cast Stuff from the Future. Join how
Speaker 1: Stuff Work staff as we explore the most promising and
Speaker 1: perplexing possibilities of tomorrow. The House Stuff Works iPhone app
Speaker 1: has arrived. Download it today on iTunes, brought to you
Speaker 1: by the reinvented two thousand twelve camera. It's ready, are
Speaker 1: you