Thursday, June 27, 2013

Learn this simple button- EV compensation/ Exposure Bias

Many times when you take photos, they come out dark and people's face are also too dark (especially on a beach or in snow) or sometimes faces get washed out (particularly when background is a bit darker).

Camera is a machine and many times, it doesn't understand what is in front of the lens. It is programmed (particularly in AUTO mode) to take say x amount of light (light is measured in Lumen but it is hard to interpret). So on a beach when everything is too bright, camera tries to take in x amount of light but that is too less to properly expose human faces. That is the reason we look darker on a beach, on snow or on a bright day. Opposite happens in evenings or in dull light. Camera tries to take in x amount of light but that exposes the faces too much causing people in the photo to be washed out.

Probably you are not aware but somewhere on your camera, you will see this icon or a button with + and - minus sign as shown below. It is called EV (Exposure Value) button or Exposure Compensation button.
Please note that some cameras don't allow EV compensation in AUTO mode. If this is the case, hopefully, your camera has P (Program) mode and you can use it with EV compensation.
Sometimes it is also referred to as Exposure Bias. Click on it and it will open up a scale or a value on your LCD.

You will see a number with + or - sign or a scale which has a value bar with values from -3 to +3 or -2 to +2 as shown below. Which scrolling button or with directional control buttons on your camera, you will be able to select any plus or minus values.

So what is the big deal about this?
By selecting a value here, you can tell your camera to take in more light or less light! This can come very handy to brighten up those dark faces or make those washed out faces more pleasant!!
To tell camera to take in more light, select any positive value. Don't rush to select too high of a value because that can wash out the whole photo! Start with +.3 or +.7 and camera will take in 30 to 70% more light. This can help get people nicely exposed in your photos.
To tell camera to take in less light, move the slider/value in the other direction. Start with -.3 and your camera with take in 30% less light!

To show this with some images, I shot the moon in the sky with my camera with different EV values or Exposure bias. With 4 different images, I can pick the one that comes out better. Probably I could have take photos of people on beach to show this more effectively. However with these photos of the Moon, you can see how camera takes in less light with my pressing of the EV button!
Luckily my Pentax K-01 took the right exposure in the AUTO mode but take out your camera tonight and try to take a photo of the Moon in Auto mode. Mostly it will be washed out. Then start with negative EV values and at some value,  you will have a nice capture of the Moon!
It is not the camera that always takes good photos! Many times it is a little help from the cameraman that helps camera take a nice photo.