To continue on the previous blog about focusing. Let's talk about the different ways how a digital camera uses its focus. Since my focus is simple cameras, I'm only going to talk about Point and Shoot cameras. You know, those pindot-pindot or point and click cameras. No DSLR here.
There are several types of cameras from the simple no setting cameras like the Canon A470
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=183&modelid=16338
To the more complex Canon G10
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=144&modelid=17624
Note: I'm using Canon as a sample since I'm more familiar with their cameras. I'm not endorsing them or anything.
So, what's the difference between these two cameras? The number of settings you can do. The A470 has no settings, basically, you just zoom in or out and click.
The G10 has all the settings of a DSLR (pro cam) except it doesn't have interchangable lenses.
You can take great photos with any of these cameras and you can take bad photos as well. But as long as you follow certain rules, you'll have more good photos than bad ones. And the number one rule of course is knowing how to focus your camera.
So going back to the topic of autofocus.
A lot of people either buy a very simple cam like the A470 or something a little more complicated. But what I noticed was that most people put the settings on auto all the time. Even if they buy a G10, they put the dial on auto setting. That's the one with the green square on the dial.
When you put it there, that means you let the camera decide whether to use flash, how to focus, what to focus and basically, control all the settings of the camera from ISO, aperture to shutter speed (I'll discuss these later).
There's nothing inherently wrong in using this setting. But you have to know how to use it properly.
For example, you want to take a photo of a person about 10 feet away from you. If his background is a plain wall, when you focus on the person, the camera will automatically detect his face (if it has face detection) and you will see the green focus rectangle around his face even if it is not in the center of the frame.
That means, the camera automatically knows that is his face so the sharpest detail will be on his face.
This is ok and you'll take a great photo. But the problem is, most people don't even know that green rectangle is used for that!
It's rare that you take a picture of a person with a plain background, what's most likely to happen is you take a photo with a group of people or with a scenery. Sometimes though, the background is strong enough that the camera thinks that it's the main subject. So when you autofocus and especially if you have face recognition, it could focus on the background instead of the person you want to take a picture.
When this happens, you will see the rectangle focus on something other than your subject's face. When that happens, your subject is blurry and your background is sharp.
Whenever you see this happen, release the button and adjust your framing and focus again. Maybe the small movement will help the camera recognize your subject and focus on him. Once it does and you lock in the focus, you can recompose the shot again. Just remember to keep the button half-pressed while you recompose otherwise you will lose the focus again.
Comments
Post a Comment