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Intro To Flash Photography

So why do we do flash photography? Well, the thing that we're running into on the when we're shooting with the other lights, the constant lights Before, if you remember, we had issues with the ambient light that was floating around throwing off her photos, right, And we couldn't really do much about that except for turning off the lights that were around us. That's how you control constant lights. You just anything that you don't want to show up, you have to turn off. And so that is usually not something that you can do all the time. And so we want to be able to compensate for that. The other thing is, um, with a speed light or a studio Strobe, you can actually freeze action. And what I mean by that is with normal ambient light or natural light or light that's always on. You are at the mercy of your shutter speed. So if you have a slow shutter speed, you're gonna have blur with a speed light or a studio strobe. You can actually have a slow shutter speed and have a crystal clear photos,...

because the light is actually what freezes the action. Not the shutter, which is sort of cool. And so you can mix these two things. You can actually have something that's blurred in the background and something that's still in fact, we did that this morning. Make sure you this picture of Ryan really fast that we did to sort of prove this out. It was so much fun. Here it is. So we did this this morning. This is Ryan, our producer. And these are These are two sources of light. So the light that's on Ryan is coming from a speed light, and the lights that are blurred are actually these lamps that we see right here and so you can control ambient light and light from a flash. Independently. And so basically, you're getting it's similar to a double exposure. Actually, you have two different things you're controlling at the exact same time. So let's talk about how this works. We have to exposures ambient light and light from our flash, and you can choose toe, let the ambient light show up, or you can choose to eliminate that. And so when we were shooting before and we had that blue color cast coming in from the ambient light. If we were shooting with a speed light or with studio strobes, we could have actually eliminated all of that. And that's why I love using this. So let's talk about these two exposures and how they work. So if we have, um, an image like this one here, this is a shot that I took in Phoenix for some workshops. Somewhere you can see that the background in this is the same in both shuts right, the same on both shots on the foreground. This shot here has no flash on this one. We have a fill flash that's helping us out to make sure that our model is illuminated and it matches the background. And the reason that I did this was this was on a really bright, hard light, sunny Phoenix day. And so if we put our model just out in the open son, we have had these horrible shadows and she would have melted cause it was about 100 degrees when we shot this. And so we found a tree. We put her in the shade, which is this right here, and I exposed for the background. And then we added a flash and that balance those two things. And so that's one of the reasons that you might want to balance ambient light with flash because you get these really interesting exposures. All right, so, ambient light, we have to react to it, right? We can't control this. We have to just sort of take what we get. We can do some modifiers with our California sun bouncing or five and one reflectors and all that kind of stuff, but we can't control. It has this tendency of changing and so we have to be able to react to that in a certain way. In the way we react to that is by using the exposure triangle. And this is something that we all know and love. So we have our aperture value. We have a shutter speed, and we have our s O. If we have the capture that only controls quantity of light. When we're talking about ambient light, right, the shutter controls the duration of light. That's usually if a fast shutter we have frozen images. Slow shutter. We have lurid images. And then I s o controls sensitivity. That's ambient light, but we want to do is we want to forget about ambient light just for a minute, okay? To just throw it out of your mind. We're not gonna talk about that. We have these three things. We have quantity. That's how much we have duration. We have eyes. So what we really want to do is we want to focus on these two things and understand how they work with our flash. So we're gonna get rid of the I s. So and so we have these two things quantity and duration. So quantity is controlled with Anya. Light by our aperture duration is controlled by our shudder. And what we need to talk about in greater depth is that pesky shudder. What is it doing? Because, quantity, when our flash fires, it's always going to go through the aperture lens, right, that lights always gonna go to the aperture lens. But with the flash, something else is happening here. So with our shutter, it actually doesn't do anything for flash exposure. The shutter doesn't impact the flash at all. This is something that you have to get your mind around. It's important to understand how your camera's shutter works. Your camera's shutter has two curtains, and these curtains have names. The first curtain and this second curtain. They open and close to reveal light to the sensor, much like a curtain opens and closes in a theater to reveal what's happening on the stage. Let's take a closer look when you press the shutter release with your finger. It tells the camera to open the shutter. The first curtain opens to reveal the light to the camera's sensor. Then the second curtain follows behind to hide the light. Then the curtains reset and wait for you to press the shutter release again. Let's watch that again. Noticing this animation that the first curtain opens completely before this second, Kern begins to follow. This only happens at slower shutter speeds, usually speeds under 2/100 of a second. Now watch what happens when we speed things up. When the shutter speed is faster, the second curtain can't wait for the first curtain toe open all the way. If it does, it won't make it across in time. Notice in this animation that the shutter is never fully open, it just reveals a slip of light as it travels across the sensor and the slit becomes smaller as the shutter speed increases. Sync speed is the shutter speed on your camera that allows the first curtain to fully open before this second, Kern begins to follow. In other words, it's the fastest shutter speed you can use with a flash. Let's take another look at your camera shutter, this time with a flash in the mix. When your camera shutter speed is set to sync speed or slower, a few things happen when you push the shutter release button. The first curtain opens, and as soon as the first curtain is fully open, the flash fires. Then the second curtain closes. Normally, if we have our shutter speed set too high, we'd have problems. Let's take a look. When you press the shutter release, the first curtain will begin to open, but before it's fully open, the second curtain begins to close. When the first curtain is fully open, the flash fires just like it did before. But this time part of the sensor is covered by the second curtain. This will cause our photo to have a black area, and the faster your shutter speed, the more black you'll have in your photo. We're only talking about light from the flash so the shudder still impacts ambient light. We're just talking about light from the flash. Don't forget that. So what controls are flash exposure if our shutter isn't involved, We have a new exposure triangle toe work with here, and it's sort of fun. So we have duster our aperture and output from the flash. So our aperture is still gonna control. Light is gonna be smaller or larger to let in more light or less light, and that is going to impact. Ambient light and light from the flash shutter doesn't do anything cause it's always open. But the flash itself has different power settings, so the flash can have less power or more power. And so that's what controls the exposure. In fact, in on a speed light, it can only get so bright. And so there are times when you have a huge soft box, it doesn't have enough power, and you're gonna be under exposed because there's just not enough light coming through there. So that's why studio strobes work out. So the flash exposure triangle looks like this. We have our aperture value, and er is so and then we have flash output instead of shudder and that flash output does something. So the aperture now is going to control the quantity of light just like it did before Dept. The field, all that kind of stuff. The flash output actually controls quantity. How much light? And it controls duration, and so are shutter used to control duration for ambient light. The flash output actually controls duration for our, uh, our stroke. So here's how it works. That shutter opens up the strobe fires boom on and off, and the strobe fires at speeds of 5/1000 of a 2nd 10/1000 of a 2nd 20/ of a second. It's pretty fast, especially with speed. Lights are really, really fast. And generally the lower the power that shorter the duration of light is. And so if you have a completely dark room and let's say the shutter opens and it's open for five minutes and it's completely pitch black, so the shutters open for five minutes. But the flash turns on and off, and it does that at 2/100 of a second. How much light did the camera actually see? It only saw 2/100 of a second of light. And so it's the equivalent of having a shutter speed of 2/100 of a second or 1/1000 of a second or 5/1000 of a second. If you've noticed your camera shutter speed usually goes up to about 8/1000 of a second, and that's it. But one of these guys can shoot the duration of about 20/ of a second, so you can actually have a really dark room and use a speed light or a really fancy studio strobe and freeze action better than the fastest shutter speed that you have on your camera. Well, we're talking about flash. Generally, what people will tell you is the aperture controls the flash exposure, and the shutter controls the ambient light exposure. That is not exactly true, because the aperture is still going to impact the app of the ambient light. But what you can do, though, is slow the shutter down to get mawr ambient light and speeded up to get less ambient light. All right, things we have in common good, um, with ambient light. The shutter controls the duration of light with a flash. The flash output controls the duration of right light with ambient light. Aperture controls the quantity. It still controls the quantity in a flash with ambient light. Eso controls the sensitivity, and it also controls the sensitivity in a flash. And so let's say the opposite is true, that you're trying to shoot with a large soft box or something, and you don't have enough light. So it's not the neutral density problem. It's We just don't have enough light to illuminate the subject, because the flash can't throughout enough light. Well, you can do a couple things to help that you can just increase your eyes. So and that is going Teoh, make the flash of the camera more sensitive to the light from the flash and the light from the ambient exposure. And so what you would do is, let's say your flash outputs at 100% and you're under exposed by a stop. You could increase your eyes. So from let's say, I s 0 102 100 now you're flash is gonna be just fine. And then you would take your shutter and you would increase it by a stop. Teoh compensate for the difference in that, Or you could compensate by changing your shutter by a stop. But if you do that, guess what? Now you're flash has to have more output because the aperture is also controlling the flash that makes sense. So you're like, Oh, well, this increase my s o. And then I'm just fine. But what you'll find is now the flash is fine. But now the ambient light is overexposed. And if you don't have enough room to go on your shutter, then you've got another problem, so you might have to keep doing those adjustments. So it's it's good to know what happens when you adjust each of these things.