Exposure Triangle: Shutter Speed
We're gonna begin with understanding exposure. Why is that so crucial? Well, let's say you're on vacation on a once in a lifetime trip in the desert. This is the Sahara Desert, a pretty amazing place in Morocco, not the kind of place you can just get to on a whim. And if you're trying to take a photo, you might end up with this. And I would say that didn't really represent our experience very well. And this is what happens if you're just pointing and shooting and not really thinking too much about how the camera's gonna read the environment. This is what you can get in the same environment with the same camera, which by the way, this was just a little point and shoot compact camera that fit in my pocket, and this is the result that I could get when I bossed the camera around. We're gonna be learning about how to control exposure so we can get better results. We're also gonna be learning the creative impact. So not just being able to get an exposure that is quote acceptable or good, but...
being able to creatively control the exposure. What kind of exposure do we want? So here is an image with everything frozen in time. Here's the same scene photographed with some different settings that yield a different result. So we're gonna talk about how that happens. Here's another photo, this is my cat Emka (laughs). She's handy, I was trying to get some sample photos of my son Zay, but he is a toddler and he wasn't interested in cooperating, but the cat, who was desperate for attention these days, was right on board. Here we see a photo of her shot one way, and we can see her and all of her beauty and we also see the messy area behind her. Here's the same scene now photographed with different settings and now we see her and the background just becomes a yummy blur. Those are different exposure settings. Knowing what they do and how to use them, you can control your image that you get and get different results. What do we have to know? Well thankfully it's only three things. Just three things that make up exposure, ISO, shutter speed, and aperture. It's just those three things. The thing, too, to know about them is that it's important that they balance. Unlike math class, where two plus two is four, and it's always four, exposure can be very different however you want. You can adjust it. You can play with it. There is no right answer. This is a balancing act. The combinations can be whatever you want, as long as you get the result that you are looking for. Before we get into how the balancing works, let's just talk through these three things and how they impact the image. We're gonna start with shutter speed. If we think of exposure, first of all let's define exposure. Exposure just means the picture, and the combination of settings that resulted in that picture. An exposure means a photo. I took three exposures of my cat, so I would have three pictures of my cat. They may have different settings, each exposure may have a different setting. They may all be quote correct, and they may all be very different. There's no right answer, again. So that's what exposure means. If we think of our cameras as our eyes, what part of our eyes do you think, you might wanna grab the microphone so you can be ready to answer, 'cause I know you're gonna know this, what part of our eyes do you think would be similar to the shutter of the camera?
Would that be our eyelids?
That would be our eyelids, yes. Think of our eyelids like the shutter. Our eyes blink open and shut, and we see when they're open. The camera also sees when the shutter is open, so most of the time it's closed. It blinks open and blinks back shut again, and that's what the shutter does. You can control the shutter speed, meaning how quickly it opens and closes, and it turns out that that speed has an impact on the way that time and motion is captured in the resulting exposure or photo, right, in the resulting photo. One way to think of it is the shutter speed controls how much time you're gonna capture in a photo. You can capture a super quick sliver of time, or you can capture 20 minutes, an hour, three days. I don't know, I've never shot a three day long photo, but I'm sure someone somewhere has. But you can capture long moments of time in a single photo if that's your choice, and it's the shutter speed that controls that. So that's kind of a funny way to think about it, 'cause when we think about photos, we always think of like an instant, but you can control how big or small that instant is. So that is called our shutter speed, and Gabby has a question. Gabby?
Would the shutter speed be, if you wanted a long picture, would it not blink, so to speak? Or would it just kind of be like a video recording in a way?
It would open, well we'd have one frame. So a video, when a video records, it takes a lot of tiny pictures on multiple frames. In this case, the shutter would open and then it would just be like your eyes, like open without blinking and then eventually close. It's one big blink. Good question, yeah. And it turns out that the various speeds are measured something like this. This list is not an all-inclusive list of every possible shutter speed, I just picked some and put them up on a little continuum so you can get an idea of how it works. They're typically measured in fractions of a second because it's usually fast, unless you're doing a long exposure or some time-lapse kind of stuff, it's usually more quick. It's typically measured in fractions of a second, so 1/15 of a second would be over here on the slower side versus 1/1000 of a second would be a faster blink. I don't even know, I don't think we can blink 1/8000 of a, I don't know, that's really fast. The camera can blink really quickly. This is on the faster side, this is the slower side. The slower that the shutter becomes, the more likely that any movement that you're pointing the camera at is going to appear blurred. You can get that motion streak, that's gonna be with a slower shutter. If you wanna freeze action, like if you're photographing a car race or a really fast toddler (laughs) and you wanna freeze them, then you wanna use something faster. It doesn't necessarily have to be 1/8000, you don't have to go home and photograph your toddler at 1/8000 of a second, that would be a really fast toddler. I don't like to give people specific numbers because there's really no such thing. It completely depends on your subject and your environment, and whatever light is happening there. Sometimes people will say okay well if I want a motion blur, what should I put my shutter at? The better question to ask is, if I want a motion blur, do I need a fast shutter or a slow shutter? And the answer, of course, would be slow. How slow? Well, it depends. You just start experimenting. When we talk about this stuff, I wanna challenge everybody to keep your minds up at the higher level where we're just talking conceptually about this, and don't get lost in the very detailed specifics of, well what exact setting should it be, what number should it be, because there isn't one and I think when people are searching for those specific numbers, they have a much harder time actually getting the results they want than if you think about okay, do I need it faster or slower, and go from there. We'll talk about how you figure that all out and how you eventually arrive at something that works for you. But that is the overview of shutter. I will also point out there's fractions of a second, and then of course on the very slower side, you could have full seconds. You could have a one second, you could have 15 seconds, 30 seconds. I think that photo in the desert that worked out, I wanna say that was a 15 second exposure. I don't recall, it's been awhile. It was long. Did it have to be 15 seconds? I don't know, maybe I could've done it in eight if I changed some other settings, but that particular photo was captured I think at 15 seconds. Here's a couple examples. Here we see this is Trafalgar Square in London, and we see some streaks from the cars. Again, not worrying about specifics, when we look at this, what do we know about the shutter speed and where it was on that scale? Would you say it was on the faster side, or the slower side?
Would say it's probably slower, maybe a second or two?
Exactly, I think it was two seconds. This is slower, we know that because we can see the cars moving and we know, with our own eyes, well we can see them moving, but if you were to close your eyes and only open them for a 1/1000 of a second, do you think you'd see the car move? No, right, you have to leave them open a little bit longer. Same with the camera. To see the car moving, the camera has to have its eyes open for a little bit longer. When I was shooting this I was just experimenting. I tried four seconds, and that actually made it like you didn't really see the cars, they drove by and left and they got sort of recorded over and it looked like they vanished. I had to adjust it to be two seconds. You just have to experiment, but yes, this is a slower shutter. We have a question?
Yeah I see some of the things kinda clear and some of them in motion.
How is that? Very good question. The things that are less streaked are not moving at all or not moving as fast. For example, the buildings thankfully weren't moving, that would be really creepy or dangerous. They're not blurred at all. We might see some cars that have less blur or more blur, and these people over here, they weren't moving a whole lot in those two seconds so we don't get much blur from them. If you tried this at home and you took a picture with a couple second shutter speed and you had one person walking across the frame and another person running, you could have different results. Of course, when you're shooting something like this with a slower shutter speed, we should also mention that you need to steady the camera on something. Whenever you are approaching some of the longer, anything from maybe, it really depends what you're shooting, but I start getting a little iffy about it if I get to like 1/50 of a second or slower. I start trying really hard to hold my breath or do something so I don't wiggle, but certainly at two seconds, this camera was supported on a tiny, miniature tripod that I had with me that fit in my purse. It doesn't have to be fancy, you don't even need a tripod, you can also set it on a table or a wall or some other piece of architecture, or the ground or whatever. It does need to be steadied because you can not hold the camera still for two seconds without blurring the scene. There are two different types of blur, there's motion blur from wiggling like that, and there's blur from not being in focus, and they're two different things. Shutter affects motion blur. Here's another example that, of course, we don't see that motion blur. We can assume correctly that this was shot with a faster shutter speed. I don't remember exactly, and it doesn't matter, the exact numbers don't matter. What matters is this was fast enough to freeze this action. And combined with the other parts of our exposure triangle, we got a good exposure. How do you find this, how do you find your shutter speed on your camera? For our purposes right now, the easiest way to have a peek at this is to put your camera in manual mode. You have your DSLR in your lap, go ahead and change your dial to M. It's not standing for monster, it's not scary, it stands for manual mode. Go ahead and change your dial to M, and then on your camera, now again, they're all different, but generally speaking on your camera somewhere you'll have a little dial near your shutter typically, and that will control your shutter speed. How do you know what your shutter speed is? One place to look is if you have a little display like this on the top of your camera, this 125 right there represents a fraction. We don't see the 1 over 125, it's just implied. If it says 500, it means 1/500. Here, 125 means 125th of a second, so that's decently fast, sort of. It would freeze my cat as she sleeps on the sofa, she's not moving too much, so that's fine. That's on a DSLR and if you happen to have a point and shoot camera that has manual mode, or somehow also allows you to control your shutter speed, you might have a little ring on the back like this. I have an old point and shoot camera that lets me shoot in manual mode and that's how I would control the shutter speed on that camera. When you look through the viewfinder in your camera, that's another place where you can see information about your exposure and your camera settings. Here this little viewfinder represents what you might see. Somewhere around there you'll see a number like 500 over there representing 1/500 again for the shutter speed. If you're at home playing with your camera, I would encourage you to put it in manual mode, fine wherever your dial is for shutter speed, and then just dial it like all the way to the left, for example, until the numbers quit changing and then try dialing it all the way to the right until the numbers quit changing, and that is how you can see what your ends are, what your range for your shutter speed is. Oh and also if you are on the slow side, if you have one second, it will instead of just saying one, it'll usually say one and it'll have inch marks. If you see inch marks, that means you're in the full second territory, not fractions anymore. That in a nutshell is shutter speed. Again, there's more settings than what we see there, that's just an assortment that I randomly picked out.