Hi everybody. Welcome to another episode of Exploring Photography right here on
AdoramaTV. I'm Mark Wallace and we are continuing our series of the basics of
studio lighting principles. These are the tools that you use to build and shape
light in the studio. Now, this week we're going to be talking about something
called the effective size of light.
It's important because it helps us determine which kind of light modifier
to use and where to put that light modifier and it determines how our light
looks, if it's hard or soft, or contrasting or not. It really has a huge impact on your
photos. Now to illustrate this, take a look at this. I have this softbox right
here and notice, it's about the same size as this umbrella right here. Or is it?
Of course it's not. If I bring it closer, look it's much larger. In fact, this
umbrella back here is much, much larger than this softbox and that is how
effective size works.
The closer your light is to your subject,
the larger effectively your light source is and that changes everything.
Now, to understand this, what I've done is I've created an animation, in fact I've
created this for my studio lighting essentials workshop. We're going to use
that here this week in this episode.
So let's take a look at that so you can understand all of these different terms
and principles. So let's take a look right now. There are lots of words that
photographers use to describe light.
Let's start by talking about two of the most common terms in studio lighting,
hard light and soft light.
The best way to tell if light is hard or soft is by looking at the shadows it
casts. Hard light casts a very clearly defined shadow.
Its edges are hard. Soft light casts a shadow that's hard to tell where it
starts and stops. Its edges are soft. On a day where the sky is clear
the Sun will throw a concentrated beam of light that will produce deep sharp
shadows on the subject.
This is hard light but if the clouds come out then the light becomes diffused.
Instead of the light traveling in the same direction, it is cast in different
directions and the source of the light becomes much larger. A larger light
source will throw a wider beam of light with shadows that are more open because
light is bouncing around and spilling into the shadows.
This is soft light.
An important term is effective size.
The effective size of a light is based both on the physical size of the light
and its position in relation to the subject.
In other words the closer light is to the subject,
the larger its effective size and the softer the light will be. The farther
away a light is from the subject,
the smaller the effective size and the harder the light will be.
To illustrate this point, let's look at the sun. Although the sun is 100 times
the width of the earth,
it looks like a tiny speck in the sky. That's because it's 93 million miles
from the Earth.
This makes the sun's effective size very small and therefore it gives off a
very hard light.
Now if we were able to move the sun very close to the earth,
its effective size would be much larger and the light it casts would be much
softer. We can change the quality of light by changing the effective size of
our light source. Since moving the sun closer to the earth would be impossible
and a really bad idea,
there is another way to modify our light source. We can use modifiers.
Now, let's bring back the clouds. In this scenario, the sun would be the light
source and the clouds would be a light modifier. The sun lights up the clouds
and the clouds become a huge light over the earth.
Now our illumination is the entire sky not just the tiny dot of the sun.
The effective size of the light is much larger and the light is much softer.
Sometimes soft light is called diffused light and hard light is called harsh
light.
Contrast is the difference between the darkest and lightest areas in an image.
The greater the difference, the higher the contrast. In much the same way, you
can change how hard or soft the light is by moving a light closer or farther from
the subject.
You can also change the contrast of your image by changing the position of a
light. When you position the light in front of your subject, you get a low
contrast lighting.
If you move your light to the side of the subject, you get a much higher
contrast lighting.
Alright, well let's put those principles into practice without setting anybody on
fire, and because we promised not to set Maria on fire, here,
she has said she would be our model for this video.
Now, what we're going to do is, I'm just going to show you a very simple
demonstration between a small light source and a large light source and
show you how the effective size changes the quality of light. Now, to do that we're
going to start with a very small light. This is a Profoto B2 head. Notice how that is
very small compared to my hand and that's going to be what we start with.
Now, I've already metered this and so I'm going to shoot this at f/8. So Maria's just
going to look straight at me and I'm going to focus this really quickly and click.
Alright, now, when we look at this you can see that that light is very hard and
directional so we have a really, really hard shadow underneath your chin. We've got
this really hard shadow on the background and that is not necessarily
what I want. I want to change the quality of my light and to do that I'm going to
change the effective size of my light
by using this Octobox. Now what this is, notice that it is larger than Maria's head.
So what will happen here is when we put this on our light, it's going to actually
surround her and so we're going to have light that's going to be falling into
the shadows.
That's going to open up those shadows and create soft light.
So I'm just going to put this on my light really fast so I'm making my light much larger,
so the effective size is larger, our light quality is going to be softer. Now,
because I put a softbox on my light, I need to re-meter this and so we'll
go in here. Now, I shot the first shot at f/8. I'm going to meter this really
fast and see if we can get that at f/8, so we're almost there.
So now, again. OK, now we're at f8 so we'll shoot that, so I'll zip over here and then,
Maria, we're going to have you look right at me again. Now,
we're going to shoot the same picture so both of these are at f/8. Get a little
closer so the softbox doesn't show up in the shot.
Perfect. OK, so now when we look at these two pictures back to back you can see
that the shadows, specifically over here, are dramatically different.
The large softbox gives us a much softer light because of the effective size of
the light. Now, what about contrast and the position of light instead of moving
my light around the light is always in relationship to the camera when we're
talking about position of life so if my light is here my camera's here if I move
my camera
it's the same as moving my light and so that's what I'm going to do so instead
of being right here
straight on I'm going to move over here to the side and so now this light is
coming to the side of maria and that's going to give us really contrast the
light and so because the light hasn't changed the relationship to our model
the metering doesn't have to change when we look at that
Wow the contrast has really gone up
so this side of her face is illuminated this side of her face is dark so our
contrast has changed dramatically
now let's go over here so Maria let's have you look straight at this light
I'm have to raise this up a little bit so I can actually shoot underneath this
i'm going to try to do this as much of the same as possible
ok so still at f/8 now i'm shooting right underneath the light so we're
right in alignment with the light so we have perfect again at f/8 and take that
shot and what a difference that makes
so let's take a look at these shots that first lot at that first shot we have
hard
contrasting light the second shot we have much softer light and we looked at
the contrast and just by changing the position of my camera which essentially
is the same thing
the changing the position
the light I'm able to take that contrast and lower it and get this really
beautiful shot
I think you'll agree that the final shot is much better than the shot we began
all right well there you have it the effective size of the light and a
position of the light really change the quality of the light now to put all of
this stuff into practice we're going to take it up a notch in the next episode
so Maria has been a fantastic model today but in the next couple of episodes
are going to really see how these lighting principles will bring our light
shaping to life so don't miss out in fact you can make sure you don't miss
out by subscribing to adoramatv it's absolutely free and your life will be so
much better if you just click the subscribe button and that way you get
all of the content that everybody produces absolutely free so click
Subscribe right now
thank you so much for joining us we'll see you again next week