The Science of Photography

August 29, 2008

Ever wondered how does digital photography work? Here’s a quick ‘science/physics’ on the mechanisms of digital photography to help you better understand and APPRECIATE the wonders of technology. Oh no, don’t you groan now, it’s not gonna be boring! :)

Okay, in principal, digital photography works very much the same way as traditional film photography.

Light passes through the lens onto a light-sensitive material called digital photo-sensor (DPS) this is also the equivalent of the traditional film.

The sensor is an array of millions of light-sensitive cells of photodiodes which respond to the light falling on it when the camera opens its shutter.

A corresponding signal is then created in which it is ‘digitized’ (aka given a number value) so that the computer, in your camera, can read it.

In essence, the sensor in your camera acts like it is painting your photograph by numbers.

Imagine taking a piece of white paper divided into a grid of several million squares. Each square has a number and if no light reached that particular square, the number would be zero and the square would be black. Once the computer reads every square, you will have an accurate black and white picture of the original scene you have taken with your camera!

And that’s! Thats basically how digital photography works in a nutshell. Don’t wanna bore you too much with the details but stay tuned for more quick lessons on photography.

We learn something new everyday huh :) Ciao!


If you ask anybody what their main problems with photography is, chances are, you will hear blurry pictures as one of their main challenges. Nothing is more annoying than getting home from a day out with your best buds or a event, and realizing that most of your photos have turned out blurry. URGH!

Well, they say the best way to solve a problem is to first find out the cause of it.

Here is something useful that I have learned from David Peterson that I hope may be just as helpful to you as it was to me!

Main causes of blurry photos:

  1. Your camera is out of focus
  2. The subject moves while you are snapping a photo
  3. The camera moves while you are snapping

Out Of Focus

An image that is out of focus will appear blurry. These days with Auto Focus, it’s unlikely that the whole image will be out of focus. More often than not, you’ll see one part of the image crisp and clear, but others (including your subject) are out of focus.

To fix focus problems, use the half-press shutter technique. Press your shutter button halfway down and you aim your camera before you take your shot. I feel that this has always improved my pictures tremendously when the camera has fixed its focus on your subject before you snap the photo.

The subject moves while the shutter is open

You can tell this cause by looking at your subject, If some parts of the subject are crisp while others are blurry then the subject has moved while the camera’s shutter was open.

You can avoid blurry images caused by subject movement by changing your camera’s settings so that your shutter speed is faster. Try switching to the sports mode on your camera.

The camera moves while the shutter is open

This is another common problem and will cause the whole image to be blurry.

When the shutter is open for a longer time, tiny movements of the camera can cause the whole photo to become blurry. Even small movements like releasing your finger from the shutter button, or your breathing can cause it. This often happens when you are taking pictures in low light setting or at night.

To solve this problem, the best way is to get a tripod or a automatic shutter device which acts like a remote control in which you press the button on the device to snap the picture without having to touch your camera ;)