We talked earlier
in earlier lessons
about shooting in manual mode
and understanding the exposure triangle.
Now, once you understand
the exposure triangle of Aperture,
Shutter Speed & ISO,
you can start, in my opinion.
To consider using
the semi-automatic modes
which are aperture
priority shutter priority.
They have different
names on different cameras,
but basically they are the same thing.
We are going to talk in this video
about aperture priority
and why you might choose to use it.
Now, with aperture priority,
you are choosing the aperture
that you're shooting at.
But you are allowing the camera
to choose the shutter speed
so the camera will workout
using 'metering'
And we will talk about the different
'metering' modes
and a different video now.
If you know, aperture priority
is the most important thing for you
that you need to control depth of field
perhaps you're taking outdoor portraits
with a relatively still subject,
and all you want to do
is control the aperture yourself
and you trust the camera.
You can let the camera select
the shutter speed for you,
but you need to understand
the compromise that you're making.
The camera may select
the wrong shutter speed for you,
but what it will do
is it will keep the level of exposure
quite consistent
as the level of light changes.
So, for example,
if you're shooting in manual mode
and you put your camera in 1/100
of a second shutter speed
and you're shooting F1.4
and it's quite cloudy.
But then the clouds clear
and the sun breaks through.
You will find that
those perfect settings you had before.
Suddenly everything's
brighter than you
want it and you will need to manually.
You're in manual mode.
Move the shutter speed in order to keep
the depth of field that you want
by not touching the aperture.
So shorten the length of time
the shutter is open.
Let less light in
to darken the image down a bit
to get back to where you wanted it.
If you're in aperture priority mode,
the camera will do that for you.
Now, you could have the camera,
as well as being
in the aperture priority mode
where it's selecting
shutter speed for you.
You would normally have selectively ISO
So you keep the images
as clean as you want.
But you can also in most cameras set Auto
ISO where the camera also has
the freedom to adjust the ISO.
Now, most of the time
and this is what would
STRONGLY, STRONGLY recommend,
if you're going to use auto
ISO is that you set a maximum ISO
so that your camera doesn't go
higher than you want it to.
Most cameras will go to the ISO early
in their adjustment process
because they know it alters
less of the image
as far as movement
and things that are concerned
now with most cameras.
You can also set Auto ISO
minimum shutter speed.
It's a fantastic setting
if you're using aperture
priority, for example.
So back in that scenario,
where you are taking
these portraits outdoors and instead of
getting brighter
it's got darker this time
from when you started .
So the camera wants to slow
the shutter speed down
in order to let more light in
and keep the ISO at one hundred.
But it's slowing it down
to 1/15 of a second,
which means any tiny
movement in your hands
is going to come through
as Blur in the photograph.
But you know that
you do not want the camera
under any circumstance
to go below 1/125th of a second,
for example.
What it will do then is it
will raise the ISO
because the shutter speed
was going to go down.
So it's a fantastic setting.
But generally, I would suggest that
if you want to use
aperture priority stick,
at least in the beginning with a fixed
ISO maybe go slightly higher
than you really want.
Obviously, everybody wants to shoot
ISO one hundred,
but ISO 200 on most
cameras is pretty clean.
ISO 400 is pretty clean,
shoot a little bit higher
to give yourself a little bit
more flexibility.
Stop the camera from dropping
the shutter speed too slow.