Hi everybody welcome to another episode
of Exploring Photography
right here on AdoramaTV
brought to you by Adorama,
the camera store that has everything
for photographers.
I'm Mark Wallace and I'm hanging out here
in Kampuchea Party Republic studio
and I have this amazing infinity wall right here.
It's a white background.
You might have something like this in your studio,
maybe you have a white roll of seamless
and this video is all about working
with this big white beast.
How do you control that?
How do you get it to go from white to gray to black?
The reason I'm making this video
is because so many people have seen me take
photos on a wall just like this
and the wall goes to complete black or a really
dark gray and I get emails almost every day
saying how is that happening?
Well that's what we're going to talk about
in this video and we're going to end with a
really amazing portrait,
so let's get started right now.
Alright well now we
have a light and we have a model.
This is Kongka and so what we're going to be
doing is I'm going to just first show you,
that we have a light, a model and our
big white background but
when I take a photo at this distance,
right here so
look right into my lens.
Beautiful!
What the heck?
The background is absolutely dark
so what is going on back there?
Well to understand that,
we need to break this down step by step.
We need to first understand
what we can do with the
ambient light because with their eyes
we see a white background but on the
picture it doesn't show up.
So what's going on?
We have to control the ambient
light, then we have to understand
something called the inverse-square law.
So we're going to do that really quickly
and simply then we're going to put
everything together to control that
background, to create a really beautiful
portrait so I'm really excited.
Let's get started.
To understand what's happening
with our white background we first need
to understand a very important principle
of flash photography and that is
when you add a flash to your photo you
actually have two exposures,
you have the ambient light,
that's light from the Sun
or light in the room like these fluorescent lights
and you have the light from the flash
and you can control those two things
independent of each other.
So the first thing we need to do
to control our big white background
is to control the ambient light.
So let me illustrate this.
So I have my flash turned totally off.
I don't have a trigger on my camera.
I have my camera set to f/9
aperture priority mode
and I've increased the ISO
to ISO 800
just for this illustration,
so let me show you what will happen here
if I take a picture just with the ambient light,
so we're going to look right in the lens
Kongka looks great.
BAM!so I take that
that's at 1/60th of a second
it's a really not a very good picture
because we don't have any flash
but you can clearly see that the camera
can see that white background
and it shows up crystal clear.
We don't want that,
we want to eliminate that
and the simplest way to do that is just to underexpose
the background, so what I'm going to do is
I'm going to change my camera to ISO 200.
That's my base ISO for this camera
and then I'm going to speed up the shutter speed
so from I think it was the 1/7th
of a second something like that.
I'm going to go to my camera's sync speed
that's the fastest speed
that my camera can use,
the fastest shutter speed that
my camera can use with the flash.
Now if you don't know about sync speed
fear not. I actually have a bunch of videos
about sync speed and I have link
to those in the description of this
video so if that's a new concept for you
just watch those videos
and it'll all make sense.
So now I have my camera at f/9
at sync speed 1/180 of a second
and at ISO 200 now let's
take that same a picture again,
so you're going to look right at me
same exact thing, click,
it's totally black, there's nothing there look
it's just blank and so what we've done
is we have eliminated the ambient light.
There is nothing that is showing up
on that white background
except the light that comes from our flash
and that means now that we can control everything
the only thing that's going to show up
on that background is the light
that comes from this flash
or other flashes
and so we can do some really groovy things
but now what we need to understand
is what happens when we move this closer
and farther away from our subject
and to the wall
and how can we make that brighter
and dimmer so we're going to do that next.
Now that we know how to control the
ambient light we need a quick refresher
on the inverse square law.
Now if the inverse square law is confusing
to you don't worry,
I've already made a video in depth about this
but let's just have a refresher.
What happens with the inverse
square law is it's the law
that illustrates how the power
of the light falls off from the source
and so it comes out really strong right
here and then it just has a little cliff
wow it gets much, much less powerful
and then it just sort of evens out
as it goes along
and so we have this really strong light
and then it drops off
and then it evens out back here
and that has a lot of implications for us
when we're shooting with a white wall,
and so Kongka, you're going to come right
back out and we're going to illustrate this
and so here's what we're going to do.
So we're going to start with you
close to this light. I'm going to turn
this guy on and we're going to shoot
with model close to our light.
Now remember the light is falling off
rapidly, so that means that the light
is much more powerful here
than it is back here
which means that she's going to be exposed properly
but the white background is going to be underexposed
making that darker
and her perfectly illuminated.
So I'm going to meter this
and so we'll do that.
I hope this meter should meter right about f/8
so we'll do that and it's exactly f/8
ISO 200 f/8 and I'm a shooting at sync speed
which is 1/180 of a second.
Look right in my lens,
beautiful,
so we're going take this shot
and it looks just like it did before.
We have that dark grey background.
Now watch what happens
remember this light is falling off,
with an evening out
so we're going to have you come back here
much closer to the backdrop.
Remember the light now is evened out
and so the backdrop,
the white background and Kongka
are both going to be exposed
about the same so I'm going to meter this again
because we don't have as much power
as we did before,
so I'll meter this.
That meters at f/3.6,
so I'm going to adjust my aperture accordingly
and we're going to take a photo,
beautiful I love that right there
and look now we have a perfectly
exposed model
and a nice white background.
That's what the inverse law
does for us,
so if you want a dark background,
you got to make sure that your
light and your model are close together.
If you want a nice white background
make sure that your light is farther away
and that your model and your white background
are closer so that, that inverse-square law
works for you.
Alright we know how to expose
the ambient light so that we have a black
background. We know how to use
the inverse square law
to control the different shades of gray
that we have on our background
let's put that all together
and make a really nice portrait
Kongka is out here she has a nice white
top and black pants
and that is going to be nice and contrasty
with the background.
We're going to let that fall into darkness,
now to do this I want soft light,
so we're starting with our fill light.
This is this giant 7' silver umbrella
that's just going to sort of shower down light.
It's going to bounce off the white floor
and fill in but we want nice directional light
as well and so we have this small softbox
and that is going to come from the side
and make sure we have fall-off
and so that's going to sculpt her cheeks
and give us some directional soft light
now because these are so far from the
background Kongka's white top
is going to contrast with this dark background,
it's going to fall into darkness
not completely into darkness,
we just want a dark gray
but that is exactly how it's going to work out.
We're going to shoot this outfit
and maybe a couple of different wardrobe changes
and I'm going to show
you the results, so let's get started right now
I love these images, I think they're soft
and wonderful. Thank you so much
Kongka Chan and you know what she won
Cambodia's Next Top Model
and if you want to see all of our amazing pictures
and behind-the-scenes stuff here is her
Instagram so you can make sure you check
that out. I want to tell you about two
other videos that I've made,
about white backgrounds.
I did one called white paper tricks that will show you
how to sculpt really interesting things on a white
background using some of the principles
that I taught today
and I also want to remind you
about the inverse square law video
that is a deep dive into the
inverse square law,
if that's a little bit confusing to you.
I have provided links
to both of those videos
in the description of this video
and a link to her Instagram account
in this video and so thank you so much.
How do you say thank you in Camia?
អរគុណ
orgoon
thank you.
Don't forget to subscribe
and we will see you again
next time.
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