Come on Tasha, up you get. Stop sunning yourself.
Come on it's time to earn that three pound fifty and the diet coke.
Come on. Tasha lean against the wood a bit. That's it just tilt your head against the wood
and stare dreamily about there, somehting like that
excellent. this is an exercise to help you understand which focal length you
need
first thing you gotta do is to know what different focal lengths will make a picture
look like so what we gonna do is take the same picture
of Tasha over an over again but using
different focal lengths now this is one you can do at home
and I really recommend you do because it'll help you get your head around it
You've gotta be very careful with your composition, you've gotta make sure you do this exactly right.
Now i'm not gonna change anything here, not the exposure, nothing
all im gonna do is change the zoom, So i'm gonna shoot a picture here
of Tasha, I want to give her about that much space above her head
and the bottom edge of the picture is gonna be where this strap
meets her dress just there okay I'm going to be looking along these beach huts
and in the viewfinder i've got my little grid display on and
so i'm gonna make sure i put the edge of the beach huts in the same place in
the frame each time.
so this is what I mean there's a lot of checking to do. Now then, 18 millimeters
first
so 18 millimeters, i'm gonna get right in close, right into Tasha's
personal space
now notice i'm not zooming myself backwards and forwards to get the
magnification in the place I want. Tasha's the right size.
I'm gonna move myself to the left just slightly, i need to line up with the edge of the beach
huts
and perfect. Next one.
change it to 70 millimetres I'm going to do about halfway through my range
now because I have increased the magnification, I want Tasha to be the
same in the picture
so i've gotta move back a bit.
So let's try again, taht was a good guess but a bit too far, forward a bit. Again look, don't touch that zoom.
you must learn to move yourself not zoom the lens, there we go. Tasha is now
the right size,
just in here a bit to line up the beach huts and only perfect.
I know i've just changed cameras but infact i'm just changing lenses. They're identical
cameras.
That's how I work to save time on a shoot, is I just have
two identical bodies with longer lenses. Now I'm going to the 210 mill end
going right at the end my focal range.
I'm using the same aperture which insidentally F8
I haven't changed anything,now take the same picture.
So, oh this is much longer so I'm gonna go back quite alot because i've got much more
magnification this time. Focus on tash,
bit too far. Right.
Okay now i've got the strap on the dress, i've got the
end of the beach huts in the right place, and shoot the picture.
Excellent that worked really really well.
Now let's just have a look at these three.
now let's go for the first one
that's, uh. That one.
Looks goofy, such enthusiasm
as you can see a wide angled lens is not at all flattering it's pulled tasha's
features, it's pulled her face right forward,
but it's not very nice at all. But look around the rest of the picture
the beach huts are kinda going off into the distance like that
you can see a bit a bit of the sea, and you can see a bit of the pier but
they're very very tiny off into the background, it looks like it's a very long way away.
let's now go to the seventy millimeter shot.
if you flip between, there's really quite a difference isn't there,
so you look much much nicer you look normal.
Your face is the right shape, the becah huts have sort of straightened up,
they're vertical and they're sort of going off into the distance in the correct
fashion.
But look of to the sea, we've now lost the sea
and the pier head which was a tiny little dot earlier on
has now become much bigger, just flick between the two again.
Everything's kind of jumped forward a bit,
and in the final shot, i'm gonna put this on the ground because I hate dangling things on
camera straps.
The long lens shot, we've actually
lost the sea altogether that's gone
the pier head building is now occupying almost the whole of the
left hand corner of the frame, we've lost almost all of the sky
and you are really sharp in the picture but almsot everything else
is a little bit soft and fuzzy. Three very very different images
of exactly the same thing, and all we've done is change this focal length.
Let's just recap, let's really pull this apart and see wha's going on.
When you change the focal length you're changing three different things,
you're changing depth of field, that's how sharp,
how much sharpness goes back to front in the picture the longer your lens is
the shallower your depth of field will become, regardles of which aperture you use.
we're changing the field of view, that's how much you're getting in from side to
side like this.
the short 18 millimeter lens is including lot's of things,
that's why we could see some sea and the pier in it,
we're also altering perspective, now perspective is how close together things
appear. How crunched up they are.
Now the 18 millimeter end of things, stuff appears to be a really long way
apart, it makes spaces look bigger than they really are, and thta's how an estate agent will
make a pokey little room look enormous.
So in the 18 mil shot, it distorts things aswell so things that are close to the
lens
or near the side of the shot they will really get bends and distorted.
That's why Tasha's face was pulling out like this.
So the wide lens has extended perspective, it's made the beach huts go
off forever, it's pushed the whole pier way way back and
it's included loads of stuff to either side. The 70 mill lens
has closed that field of view a little bit and it's brought everything a little bit
closer
and this is roughly how we see the world.
Also the depth of field between the 70 and the 18
isn't massively different but it is noticeable if you look for it
then when we go to the final image at 210 millimeters,
field of view has really closed up. We've lost all the pier pretty much,
we're just looking straight up the promenard
and we're seeing a bit of the pier head building and the cliffs beyond
and they have really magnified in close.
perspective is totally flattened, the beach huts have all jammed together
and Natasha has become the absolute focus of the picture
because depth of field has shrunk massively, and because i have focused on tasha
she's really sharp,
but virtually nothing else is. So that's how you can find out
what the different focal length's
do to your picture, go out and practise that for yourself, that's really important.