Name: 高速同步及其工作原理--燈光教程 (High Speed Sync and How it Works - Lighting Tutorial)
Uploaded: 2021-01-14T06:57:22.000Z
Duration: 6 min 29 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

Here we go high-speed sync. How to set it up and how to make it work. Beautiful

girl, high-speed sync, how can you go wrong?

Hi. This is Jay P Morgan. Today on The Slanted Lens, we're downtown Los

Angeles. We're going to do a little shot of beautiful Angela Whitworth here looking

back into downtown. We're going to high- speed sync our Baja B4s. The reason we're

going to do that is that we want to crush the background a little bit. We want to

have control of our shutter speed. So we'll be able to shoot at a thousandth

of a second. That means we can open up the aperture, make it pretty wide open, gives

us a nice highlight with our strobes on her face. So we'll see the big buildings

in the background and test this high-speed sync on the Baja B4.

Why high-speed sync? To understand high-speed sync we need to understand how

shutters work. Shutters are two curtains that open and close. The first curtain and

then the second curtain. At speeds slower than 125th of a second, sometimes 160th

depending on your camera the first curtain opens and stays open until the

shutter closes. Then the second curtain closes. That's for

slower speeds than 125th or 160th. At shutter

speeds faster than 125th of a second, the first curtain of the shutter opens

and before it can completely open the second shutter starts to follow behind and

close. This means that there's no time that the sensor's open for light all at

once. A small opening is traveling across the sensor exposing it as it goes. If

your strobe goes off during this time, it shows a black bar on the bottom of the

frame. The way high-speed sync solves this problem is it starts firing the strobe in

pulses as the first curtain opens and it continues to pulse until after the second

curtain closes. This pulsing is happening so fast that the sensor perceives this as

to high-speed sync? Why do we use it? First off this keeps your

strobe synced with your camera at faster shutter speeds. This allows you to shoot

with a wide open aperture in bright light situations giving you a nice, shallow

depth of field. Because you can keep speeding your shutter up to make the

background go darker and darker. You can also light your subject with strobe

light and then use the shutter to darken your background. So the person stands out

ambient light and we match the aperture to the power of

the strobes. So if we choose "F5" now we can move our shutter speed faster and

faster to make the background dark enough to either let the person stand out or to

make it dark enough so that it matches the strobe light on the person's face.

High-speed sync give you complete control of your strobes at all shutter speeds.

So what's the downside of high-speed sync? First of all it takes more power. I lost

about a half a stop on the Bajas when we went to high-speed sync compared to full

power without high-speed sync. So you lose a little bit of power. Some strobes

may lose more than that. I don't know. But know that you're going to lose power when

you go to high-speed sync. And with more power you're going to use your battery up

a little quicker. But you know what? In comparison to what you gain with

high-speed sync, it's a pretty nice trade off. So let's

get our Baja B4 set-up for a high-speed sync. The first thing we're going to do

is turn it on. That's a good place to start, turn it on. Then we're going to hit

the RPT button until it goes to H1. It's going to show us now we're in high-speed

sync. We now have the ability to dial this up or down. We can go up to H7 which is

the most power the Baja will give us in high-speed sync. And we can dial it down

to H1 which is the lowest power that it will give us in high speed sync. We're

going to keep it on H7. That will give us the ability to shoot at thousands of a

second which will allow us to crush the background just a little bit and shoot it

a little more wide open with our aperture.

Last of all, you need to push the plus that's on the remote that sits on your

camera so that the high-speed sync will connect with the Baja B4. Let's take a

look at our shoot downtown. In Los Angeles, you can get a permit to shoot on

the streets. You can't be on private property and you can't block the sidewalks

but you can shoot on most all of the sidewalks. It's pretty reasonable.

Our camera setting's are 320 ISO, 1500th of a second and F4.5.

We're going to make our background blue by simply putting our white balance on

tungsten and then putting a full orange on the strobe. So let's get this all together

and kind of see what's going to happen here. We're going to shoot a lot of

different shots. We got a couple of mirrors we're going to put in place just

to see how she looks next to the mirrors. We'll do some without the color crossover

and some, most with. I like the look of the color crossover. It looks really nice

down here. Let's look at our lighting breakdown. Our key light is a medium,

silver line softbox. I's going to give us a really nice highlight on her skin.

I'm going to allow the shadow exposure to be bright enough so that it shows blue

into the shadows on her face. That's it. One Baja B4, dome light medium softbox

of the images unretouched. You know it's so nice to be out and not have to worry

about power. The battery powered strobes these days are just fabulous.

I then put on a 15 to 30 millimeter Tamron lens and shot some more images.

I added a second Baja B4 as a rim light on the camera right side.

And then we took a mirror that we had flipped it upside down, put it up

underneath her chin and reflected just a little bit of white light back into her

face. Here's a quick lighting buildup. Key light, a rim light just the white backside

of the mirror became a reflector card that bounced a little light underneath

her chin. Here's some more images with that three light setup.

I then took one of the images into Nik Software and I put a bi-color filter on

it. So I put a little bit of green in the corner. And that kind of gradates a little

more blue up in the upper corner just thought that was interesting.

I hope you learned something about high-speed sync today, how we can control

the background with the shutter whether that's long or short.

So check it out. Use that high-speed sync.

Post-note: The reason I like high-speed sync on a mono-block compared to those

little tiny flashes is that you got enough power to do something with.

Keep those cameras rolling. Keep on clicking and don't forget to buy one of

Don't estimate a loan. Don't stand out in the cold all by yourself trying to put

together an estimate? Go to The SlantedLens.com/estimating. I've got a

digital download that will teach you everything you need to know. You don't

Hi, this is Jay P Morgan. I'm a short man on a box with a tall woman. Stay tuned

it's going to be exciting. Is that good? Kate? Are you loving it?