Another fellow photographer experience.
When I was 16 and drove a car for the first time, my teacher took me to a large parking lot. He asked me to floor it as fast as I possibly could across the parking lot. This was my first time driving! So, I went for it. I felt like I was FLYING! Then, he told me half way across the parking lot to look at the speedometer. I was only going 10 miles per hour (16 kilometers)! The point is, the first time you try anything, it feels intimidating and like you’re out of control.The first time any of my students use a camera in manual mode, I can see them terrified to try it out. However, shooting in manual mode really isn’t as difficult as it may seem. To understand manual mode, the example below will be helpful.
I took the picture above while at a photography conference in San Francisco. In a situation like this, the bridge isn’t going anywhere, the bay isn’t going anywhere, the chain in front of me wasn’t going anywhere… I had a captive audience to say the least. In situations like this, I always use manual mode. I then set my shutter speed to 1/100. I set my ISO to 100 because I wanted no noise in the picture and I knew if I needed more light, I could just slow down the shutter speed.
After taking the picture with the settings above, I realized that the picture was coming out a bit too dark with 1/100 shutter speed. So, I slowed it down to 1/60 and it looked just how I wanted.
The point is that, eventually, you’ll find yourself wanting to shoot in manual mode for situations where you aren’t rushed to get the shot. If you’re shooting sports, outdoor portraits, or other things, then aperture priority is simpler and faster than shooting in manual mode.
Aperture
Aperture
is often the most difficult concept for people to grasp when they're
learning how their camera works, but it's pretty simple once you
understand it. If you look at your lens, you can see the opening where
light comes through. When you adjust your aperture settings, you'll see
that opening get bigger and smaller. The larger the opening, or wider
the aperture, the more light you let in with each exposure. The smaller
the opening, or narrower the aperture, the less light you let in. Why
would you ever want a narrow aperture if a wider one lets in more light?
Aside from those situations where you have too much light and want to
let less of it in, narrowing the aperture means more of the photograph
will appear to be in focus. For example, a narrow aperture is great for
landscapes. A wider aperture means less of the photograph will be in
focus, which is something that's generally visually pleasing and isn't
seen as a downside. If you've seen photographs with a subject in focus
and beautiful blurred backgrounds, this is often the effect of a wide
aperture (although that's not the only contributing factor—remember,
telephoto lenses decrease depth of field as well). Using a wide aperture
is generally considered the best method for taking in more light
because the downside—less of the photograph being in focus—is often a
desired result.
Aperture is
represented in f-stops. A lower number, like f/1.8, denotes a wider
aperture, and a higher number, like f/22, denotes a narrower aperture.
Lenses are often marked with their widest possible aperture. If you see a
lens that is a 50mm f/1.8, this means it's widest aperture is f/1.8.
The aperture can always be set to be more narrow, but it won't be able
to go wider than f/1.8. Some lenses will have a range, such as
f/3.5-5.6. You'll see this on zoom lenses, and it means that when the
lens is zoomed out to the widest position it's f/3.5, but when it's
zoomed in all the way it can only have an aperture as wide as f/5.6. The
middle changes as well, so halfway through the zoom range you'll end up
with a widest aperture of about f/4.5. An aperture range is common with
less-expensive zoom lenses, but if you pay more you can get a standard
aperture throughout the range.
That's
pretty much all you need to know about aperture. The important thing to
remember is that a wide aperture, like f/1.8, lets in more light and
provides a shallow depth of field (meaning less of the photo appears in
focus). A narrow aperture, like f/22, provides deeper focus but lets in
less light. What aperture you should use depends on the situation and
the type of lens you're using, so experiment to see what effects you get
and you'll have a better idea of how your aperture setting affects your
photographs.
Shutter Speed
Expand
Photo by Digi1080p
When you
press the shutter button on your camera and take a picture, the aperture
blades take a specific amount of time to close. This amount of time is
known as your shutter speed. Generally it is a fraction of a second, and
if you're capturing fast motion it needs to be at most 1/300th of a
second. If you're not capturing any motion, you can sometimes get away
with as long of an exposure as 1/30th of a second. When you increase
your shutter speed—the length of time where the sensor is exposed to
light—two important things happen.
First, the
sensor is exposed to more light because it's been given more time. This
is useful in low light situations. Second, the sensor is subject to more
motion which causes motion blur. This can happen either because your
subject is in motion or because you cannot hold the camera still. This
is fine if you're photographing a landscape at night and the camera is
placed on a tripod, as neither the camera nor your subject is going to
move. On the other hand, slow shutter speeds pose a problem when you're
shooting handheld and/or your subject is moving. This is why you
wouldn't want a shutter speed any slower than 1/30th of a second when
photographing handheld (unless you're known for your remarkably still
hands).
In general,
you want to use the fastest shutter speed you can but there are plenty
of circumstances where you'd choose a slower shutter speed. Here are a
few examples:
- You want motion blur for artistic purposes, such as blurring a flowing stream while keeping everything else sharp and un-blurred. To accomplish this you'd use a slow shutter speed like 1/30th of a second and use a narrow aperture to prevent yourself from overexposing the photograph. Note: This example is a good reason to use the Shutter Priority shooting mode discussed in the previous lesson.
- You want an overexposed and potentially blurred photograph for artistic purposes.
- You're shooting in low light and it's necessary.
- You're shooting in low light and it's not necessary, but you want to keep noise to a minimum. Therefore you set your ISO (film speed equivalent) to a low setting and you reduce your shutter speed to compensate (and let in more light).
These
aren't the only reasons but a few common ones. The important thing to
remember is a slow shutter speed means more light at the risk of motion
blur. A fast shutter speed means low risk of motion blur while
sacrificing light.
ISO
ISO
is the digital equivalent (or approximation) of film speed. If you
remember buying film for a regular camera, you'd get 100 or 200 for
outdoors and 400 or 800 for indoors. The faster the film speed the more
sensitive it is to light. All of this still applies to digital
photography, but it's called an ISO rating instead.
Expand
Photo by CNET Australia
The
advantage of a low ISO is that the light in a given exposure is more
accurately represented. If you've seen photos at night, the lights often
look like they're much brighter and bleeding into other areas of the
photo. This is the result of a high ISO—a greater sensitivity to light.
High ISOs are particularly useful for picking up more detail in a dark
photograph without reducing the shutter speed or widening the aperture
more than you want to, but it comes at a cost. In addition to lights
being overly and unrealistically bright in your photos, high ISO
settings are the biggest contributors to photographic noise. High-end
cameras will pick up less noise at higher ISOs than low-end cameras, but
the rule is always the same: the higher you increase your ISO, the more
noise you get.
Most
cameras will set the ISO automatically, even in manual mode. Generally
you can stick with the same ISO setting if your lighting situation
doesn't change, so it's good to get used to setting it yourself. That
said, sometimes lighting changes enough in dark, indoor settings that
letting the camera set it for you automatically can be helpful—even when
shooting manually.
Combining the Settings
In manual
mode you set everything yourself (except ISO, if you set it to
automatic), so you have to think about all three of these settings
before you take a photograph. The best thing you can do make this easier
on yourself and hasten the decision is to give priority to one of the
settings by deciding what's most important. Do you want to ensure a
shallow depth of field? If so, your priority is your aperture. Do you
want the most accurate representation of light? Make ISO your priority.
Do you want to prevent as much motion blur as possible? Concentrate on
shutter speed first. Once you know your priority, all you need to do is
set the other settings to whatever is necessary to expose the right
amount of light to the photograph.
In manual mode your camera should let you know if you're over- or
under-exposed by providing a little meter at the bottom (pictured to the
left). The left is underexposed and the right is overexposed. Your goal
is to get the pointer in the middle. Once you do that, snap your photo,
and it should look just how you want it
No comments:
Post a Comment