Photography Basics

Most people use their cameras with only the most basic function.  They leave the mode selector in automatic, point and shoot.  While this works for taking basic pictures, our cameras have so much more for us.  So the mode selector has a picture of a flower, and a little running guy, maybe a portrait icon too;

these default settings offer some advantage over the generic automatic.  They still make basic assumptions and take the decisions away from us.  This article is going to give you the knowledge and confidence to move on and make some decisions for your self.

Down to the basics.

Photographers use a few basic terms that might be confusing if we don't speak the techie language.  The four most common are probably: ISO, aperture or F-stop, focal length and exposure.  In automatic mode the camera calculates these for you and shoots.  Let us learn what they are and how to use them. Then, maybe, we can venture into the manual mode...


International Standards Organization. Yep it is the same ISO you see when you burn a CD.  When we say ISO in photography, we are referring to film speeds or sensitives.  When camera manufacturers switched to digital, they

carried the term over to help film photographers transition to digital.  The ISO number refers to how sensitive the camera is to light or how long the shutter has to let light in to take a picture.  The higher the ISO number, the less light needed to take a picture. The trade off is the less light needed, the lower the quality of picture. ISO 100 needs lots of light to take a good picture, but yields good quality. ISO 1600 will take a picture in a darker room but may appear more grainy.


Full Stop or aperture is how big of a hole the lens has to let light in the camera.  The lower the number, the bigger the hole.  The bigger the hole the

more light we let in. Like with the ISO above, more light equals faster pictures.  The trade off for aperture is lower aperture takes pictures fast and with less light, but your depth of field is shorter.  In other words, a high aperture number allows more of your picture to be in focus at the cost of needing more light.

Focal Length

This is simple lens math.  Think of the focal length as zoom power.  The higher focal lengths offer more zoom.  Higher focal lengths reduce the amount of light the lens passes; however for practical purposes this reduction is 


Exposure time. Remember exposure as the amount of time you are taking a picture.  This is how long the shutter is open in seconds.  Sounds too simple... So we will change 1/100 of a second into a exposure of 100.  1/60 = 60. And 1 second will be 1". There now it makes less sense.  

Put it all together.  

If you remember from the ISO, photography is all time and light.  The lens has a hole in it (aperture) that lets light pass through for as long as the shutter is open (exposure), this light hits the film/sensor (ISO) in the camera.  And we have a picture.  Now we can apply this:

Total Light = Exposure time + Aperture - ISO

To make things as simple as they can be, the total light is not going to change.  We will change the other three.  But as you can see if you change one of the three the other two have to adjust so the total light can stay the same.  If the ISO is set higher we need less time (exposure) or less light (aperture) to get the same total light.  These three settings interact with each other to control the picture. Each with its own trade off.

Lets use the aperture settings here.

Details on using shutter speeds.

Save the picture with ISO settings.