Demystifying ISO

What Is ISO?

ISO is simply how sensitive the sensor is to the light that it records.  1 stop increments of ISO are as followed: 100,200,400,800,1600.  In the film age, you would have to physically switch rolls of film out that have different ISO speeds, but now in the digital age, you can simply select it on your camera.

Shortly I will post something that relates every in basic knowledge together (aperture, shutter speed, and ISO)

Demystifying Shutter Speed

What is Shutter Speed?

Shutter Speed (SS) is the time it takes for the mirror to go up and down.  While the mirror flips up, the sensor (the object that records the image) is exposed.  When the mirror flips back down, the sensor stops recording the image.  The longer the shutter speed, the more light that hits the sensor.  Have you ever seen a picture that has a river or waterfall that the water looks this and wonder how its done?

Well it is done by having a slow shutter speed.  Due to a slow shutter speed, the sensor records the water flowing and the final result is like the picture above.  If you take a picture of a flowing river like this with a fast shutter speed, it will look dull and uninteresting.  For sports, you generally use a fast shutter speed so there is no blur in your picture.

The general rule of thumb for taking pictures that have no blur in them is that you double the focal length you are using and use the reciprocal of that that.   For instance, if you are at 200mm, your shutter speed should be 1/400.  However, if you have image stabilization in your lens, you can use a slower shutter speed and still get a shot with no blur.

I will explain more about how/why to use a slow shutter speed in a post that will be coming soon that links everything together.

Hope that helps!

Demystifying Aperture

How Does Aperture Affect Your Pictures?

Have you ever wondered what many refer to f-stops or f-number...Well I am going to explain how these terms apply to you.  All lenses have a variable or constant aperture.  A variable aperture for example would be f/3.5-4.5.  What that means is that at the lower end of the zoom, it starts at 3.5 and as you zoom in more, it gradually increases until it finally maxes out at 4.5.  A constant aperture for example would be f/4.  This means that throughout the zoom range, it remains constant at f/4.  What do all these numbers mean to you?

First off the the f-stop goes from 1,1.4,2,2.8,4,5.6,8,11,16,22...going from f/1-2 is 1 stop and going from f/1-1.4 is .5 stops

These numbers simply mean how much light the lens can let in.  What this means is that f/1 gathers twice as much light as f/2 and three times as much light as f/4.

Most prime lenses (lenses that have a fixed focal length ex: 50mm) have a lower f-stop and therefore can let in much more light.  Also since it can not zoom in and out, it has a constant aperture.

Most zoom lenses (lenses that can zoom in and out ex: 18-55mm) have either a constant or variable aperture.  Constant aperture zoom lenses are more expensive than variable aperture.

You can always increase your f-stop, but if your lens says f/4, it can't go down to f/2.8..

In a later post, I will give techniques on how to use iso, aperture, and shutter speed to achieve the pictures you want...