How is an image created?

George Eastman once said, “Light makes photography. Embrace light. Admire it. Love it. But above all, know light. Know it for all you are worth, and you will know the key to photography.”

Working of a Camera

What is Exposure?

Exposure is the total amount of light allowed to fall on the image sensor. A picture can be over-exposed, under-exposed and accurate exposure.Comparsion of exposure of image

  1. Over-exposed- Too much light creates an over a bright image.
  2. Under-exposed- Too less light creates an under-bright image.
  3. Accurately exposed- The sufficient amount of light creates a perfectly exposed image.

 

 

Exposure is controlled by three factors i.e.  ISO, aperture and shutter speed also known as the exposure triangle.ISO aperture Shutter Triangle

What is Shutter Speed?

Shutter speed is also known as “exposure time”. It is the time duration for which a camera shutter is open to expose light into the camera sensor.

  • Long, Slow shutter speeds = more light.
  • Short, Fast shutter speeds = less light.

Shutter Speeds

Slower — 1/30 — 1/60 — 1/125 — 1/500 — 1/1000 — 1/2000 — Faster


Comparsion of shutter speeds

What is Aperture?

Aperture is the opening of the lens.

Smaller opening = less light.
Larger opening = more light.

What is ISO?

ISO ratings determine the image sensor’s sensitivity to the light.

The lower the ISO number the less sensitive your camera is to light and finer grains. Higher ISO number is used in dark conditions to get fast shutter speeds.However, with higher ISO comes more noise and grains.

Comparsion in different ISO number

 

 

 

 

 

 

 

 

Here’s a video link explaining the ISO, aperture and shutter speed.

 

Depth of Field

DOF is the front-to-back zone of a photograph in which the image is razor sharp. Here is an example showing the shallow and deep depth of field.

Comparsion In two different DOF

You can have a better understanding of depth of field from this video-

Metering

Cameras have a built-in TTL (Through-The-Lens) light meter, which measures the ambient or reflective light on the subject that you are photographing.

  1. Matrix metering
  2. Center-Weighted metering
  3. Spot metering

ComparisonComparsion among three metering

For better understanding of metering watch this video-
]https://youtu.be/VP-FQNk-kCY

The Focal length

The distance between the lens’ optical center and the camera’s image sensor when focused at infinity.

How to check Focal length of an image

Before we get to making some awesome videos we need to know about the camera. There was a short description how a camera works. Go grab a camera! and try it all out because if you can get to grips with all of your camera controls you’ll be free to concentrate on composition and timing

Our next blog will be about what camera to use and how to get a film look at our videos. You can also learn more about cameras through our video book at wisdomtalkies.com