Shutter Speed & Flash Duration
So let's talk about shutter speed and flash duration, okay? Have you guys heard about flash duration? Has that ever come up? All right, so your flash duration basically is the speed of your light. So when a flash comes out, can I see the speed light? You have it floating around? All right. Cool. Thank you, sir.
Oh, got it right back here. Cool, thanks. So, when I take this flash, and I just go ahead and fire it, it happens pretty instantly, right? We've talked about this. When we think about photography from like the outside perspective, it's everything happens in an instant. But as photographers, we know, that instant exposure that you take the photo in could be a half of a second, or one 4000th of a second. It's the exact same thing with flash. The flash doesn't emit and make its impact instantly. It actually has its own speed. So, just like shutter speed, we have flash duration. It's basically the same thing, but they just call it something differently. So, what we'r...
e gonna talk about is how fast the speed of this flash actually is. And the power settings are going to affect the speed of the light. As you set the power settings higher, that light's gonna move a little slower, because there's more light emitting. So, think about the volume of this. Like, if this has to dump a whole bucket of light, it's gonna take a little bit longer for it to pour out, where if it just has to just a little drop of light, it's gonna get out of there pretty quickly. So the lower your settings, the faster your light's gonna be. Flash brands and price do affect flash duration. If you do like a really affordable, like an Alien B or something like that, the light's gonna be moving pretty slow. The light might be moving about one 300 of a second. And you know a shutter speed of one over isn't gonna freeze a runner, so your flash duration of one over won't freeze around her either. If you spend a little bit more money, some of the Godox ones and Phottix ones, and definitely the Broncolor and Pro Photo all have really fast flash durations. I mean, that's one of the things you pay for, is the speed of that light. And finally, when you are in the market and looking at strobes, and you know, hey, I wanna freeze product photography or splashes, or I wanna freeze athletes, you're gonna see flash durations, all the brands are gonna be like, "Ours is the fastest!" Well, okay, show me the numbers. What you're gonna look for is the t1 reading. The t1 is basically when the majority of the light is out of the flash, and how fast that is. So if you're out there in the market for them, ignore t5, t5 can be misleading. Look for the manufacturer's t1 ratings. And I'll explain what that is right here. All right, so this is what flash duration is. So the flash duration on the Broncolor SIROS that I'm using, the reason I invested in Broncolor is because they have the fastest light out there, and this is what I do for a living, I photograph fast-moving people. But this is a breakdown of if I were to go to one of the dealers, or if I were to go to B&H or something and be like, "Hey, I need a fast strobe, "show me flash duration," this is what it's gonna look like. It'll say, at, right there, power rating of 10, which is full power, this flash will give you 800 watt seconds of light, and it will move at about three hundred fiftith of a second. Well, that's not very fast. But, if you turn it down just one stop, to a power level of nine, you still get 400 watt seconds of light, and now the flash duration, or shutter speed of that light is one over 1500. That will freeze just about any runner out there. So I'm like, "Okay, if I buy this, "I can photograph any runner, "and when the light hits them, it's gonna be like "I'm using a shutter speed of "one over 1500th of a second." And look how fast it gets. When you get down here to five or six, that's as fast as your mechanical shutter in your camera can move. So your light actually starts moving faster than your mechanical shutter in your camera. That's wild. That means I can freeze motion better with the strobe than I ever could with a mechanical shutter in my DSLR. So when you get really fast-moving subjects, like bullets, and butterflies, and ballerinas, or whatever it is, you really need that speed, your light is gonna be able to do a better job of capturing the motion than most of the cameras off the shelf. So, this is what I'm talking about when it comes to flash duration. And here's an example of it in the field. So, I was photographing these dancers from the ballet company for that car photo, where they were leaping over the car, and we got out there at sunset. So we drove all the way out there, we brought all the lights, brought an assistant, and it's dark, so we're all like, "Oh, man, what a bummer. "We got like one photograph in. "I wish we could keep shooting." Well, the cool thing about these lights is they have an LED modeling light on them, so I was able to turn on the modeling light so we could see what we were doing, and the battery-powered, so I could get out there and we could start shooting again. So, I was shooting in pitch dark. I just put one light on the background, and one light on my subjects, and we're out there doing just poses and basic stuff. And then they start jumping and I'm like, "Oh no, here we go." Like, "How am I gonna be able to freeze dancers "in the pitch dark in a desert, "you know, at night?" Well, strobes. So if you look at this photo here, they were leaping and dancing, and jumping all over the place, and if you zoom in, there is not a bit of motion blur anywhere. And my camera settings are ISO 100, five point six, at one 160th of the second, so a slow shutter speed. And because we're in the pitch dark in the middle of the desert, the only thing lighting them is the flash. So, the only thing affecting the blur is how fast my light is. So, fast light in a vacuum will freeze everything. It's amazing. At the same time, if you guys out there are wondering like, "Oh my God, do I have to afford Broncolor "to be able to freeze motion?" There is an answer for that. No, not always, there are instances. But these photographs that I took of a professional volleyball player down in Florida were taken with, guess what, cheap little speed lights that go on top of your camera. So, this was actually taken with three of the speed lights, which helped a little bit. But if you look closely, every grain of sand is frozen here. Now, remember the photograph of the guy I had leaping on the beach, throwing sand everywhere? That was at a shutter speed of probably one over to freeze sand. So that means the light from my speed light is probably moving close to one over 4000 of a second to be able to freeze the sand. So, just like a fast shutter, fast flash is gonna be able to do that. Fast flash on big strobes, and then also speed lights. So, this is accessible. If you guys wanna start freezing motion with what you've got, speed lights will work. And we have a, I have a light meter that we can go ahead and we'll just, one 16th power, you got that set up?
Oh, no, your good. You can still just do a reading there. Okay, so this is a Sekonic light meter, and it is, which model is it? It's the 858. And this is a more advanced light meter. It's gonna give me an idea of what exposure I should be setting, but it also reads my flash duration. So, let's just go ahead and take that. It's, sure enough, it's telling me, If you guys wanna punch in on this, that the speed light that I just used is at a flash duration of t1, because that's the one that matters, one over 6000 of a second. So, this little guy is pumping out light almost as fast as your camera can shoot, shutter speed wise. So yeah, it's incredible how little and big strobes are all able to do it. The difference being, why Broncolor and Pro Photo are more expensive is they're able to have that speed at much higher power. That's really what you're paying for. So, it is doable with speed lights, here, and you can also do it with strobes. So, this is with the Broncolor Move, that you see right here. I was able to do a beauty dish. And what I wanted to do was get the lights farther away, so farther away I needed to turn up their power, and then the speed lights weren't enough, so that's why needed to go to a bigger strobe. And you see we're able to freeze motion here. Now the consideration I want you guys to think about is marrying the two of these, okay? So, when you start looking at this, everything that my strobe light hit is frozen. His form, the arm, but look towards the end. See how the ball starts to get a little blurry, and his feet start to get a little bit blurry? That's because the light that I was emitting wasn't hitting everything. So, where the light strikes is frozen because of really fast flash duration. What is only being illuminated the sun, like the ball and his feet and the beach and everything else, now that falls under the jurisdiction of my shutter speed, just like any other photo with ambient light would. So, anything the sun touches, shutter speed needs to freeze, anything that the light touches is gonna be frozen by flash duration. So, I'll show you some examples here in another photo shoot, but you have to start thinking now, it's like, "Okay, I'm able to freeze it, "but now I need to start wrapping my subjects in light, "because the light is what's actually doing the freezing." Because our sync speed on most cameras is what? One 200 of a second. And one 200th of a second is not gonna freeze a lot of motion. So now we need to start thinking about where we're placing our lights, what kind of coverage we're getting on our lights, and that kind of stuff. So, freezing motion with flash duration, the shots that I'm about to show you, these are my settings. I'm at ISO 100, I'm at F five point six, I'm at one 60th of a second, and the flash, I had them on a power setting that gave me an equivalent flash duration of about one 4000. So anything the strobe hits is gonna be frozen at this speed. Anything else is gonna be at that speed, all right? So, here's the shot, I got my guy. His hair isn't gelled like that, he's just leaping, he's flying straight up. And I have two Broncolor SIROS on either side, and I'm able to freeze him. He was a cool guy, he was a dancer and B-Boy and everything, so we were able to get a lot of cool poses. But I wanna show you one instance of photograph, right here, where we had a miss. Now if you just look at this photo, you think, "Okay, that's fine," all right? My lighting set up was my runner, the wall, and two of these SIROS, with the standard reflectors on them, on either side, but look at this photo, and start to look at his feet. Everything's tack sharp where the light hit, but his back foot starts to blur ever so slightly. And that's because he jumped high enough that he jumped out of the beam of light, or he kicked his photo over, or my assistant that day might've just missed that one take. So, just the little fraction of him that fell out of the spread of my strobe light started to blur. And that's what I want you guys to consider when you're out there, is making sure your wrapping your subject in light to do that. Or, there are things like hyper sync at high speed sync that we can cover in another class, that allow you to break that shutter speed barrier. And again, that's gonna be another class all on it's own, but there are ways to get a fast shutter speed and a fast flash duration. But for the sake of this class we're just gonna talk about flash.