New to photography: Exposure Trio

My previous post, New to photography: Gear, I talked about gears to start.  Now you buy your camera, read the manual, and tried some shots. Common questions I hear from newbies are: Why aren't my images look good? Why is it dark? or Why is it blurry? I will discuss some basics in photography namely the Exposure Trio.

What is Exposure?

Exposure is the amount of light that your sensor captures.  Photography is all about light. It is like your eyes. The eyes captures light. We see color, contrasts, brightness, darkness; in the same way the camera medium does, in this case the sensor. So basically photography is capturing light.

How to control exposure?

In photography, there are three main aspects in controlling exposure, the exposure trio. These are ISO, Shutter Speed, and Aperture.   Each of these three have their own commands in your dslr. That's why READ your manual for a smoother photography experience.

Now you might wonder what these trio actually do.  Here is a quick explanation of each.

ISO

ISO basically is the  sensitivity of your sensor to light.  The higher the ISO the more sensitive or more light can be captured.  High ISO has it's downside.  Current mid level dslr's now can go as high as ISO 25,600.  Whew!  But at a cost, noise.  To have a clean image, a low ISO is best and around ISO 3,200 the max (based on Nikon D7000 ISO performance), or even 6,400.   So be careful in adjusting your ISO.  Test your camera and find out at what max ISO can you get a clean image.

Shutter Speed

Your camera has a shutter.  It opens when you press the shutter release to expose your sensor to the light.  Shutter speed pertains to how long your sensor is exposed to the light coming in through the lens.  It is measured in seconds.  Current mid level dslr's have a shutter speed of 1/8000 sec. to 30 sec, and of course, Bulb mode for even longer exposures.

Shutter speed has a way with motion.  If you use a fast shutter speed, say 1/2000 sec., you would freeze the moving object.  But if you use a slower speed, like 2 sec., you'd see a motion blur.  For sports photographers, a fast shutter speed is required, to get that sharp and crisp action.  For landscape photographers, a slower shutter speed is need to get that creamy effect in running water or waves. 

Aperture

Aperture is the size of the opening of the lens.  It is designated with the " f ", example f/1.8.  Aperture controls the amount of light passing through the lens to the sensor.   It is also called f-stops.  

Most of those new to photography will be confused on how to describe the f-stop.  The larger the number, say f/16, is referred to as a small stop.  But a f/1.8, is the large stop.  Don't get me wrong, I myself get confused sometimes.

Aperture controls DOF or Depth of Field.  Meaning a smaller stop (around f/8 upward) will produce sharper image across the frame, while a larger stop (like f/1.8) will produce what we call a bokeh or blur to the background or foreground of a subject.  Landscape shooters and studio shooters shoots at smaller stops to get the detail of the entire frame while an outdoor portrait shooter shoots at larger stops to get the bokeh effect.

Whew! a lot to sink in.  If you've noticed all three controls the light that passes through the camera.  Think of it as this:

ISO - how sensitive to light

Shutter Speed - how long the light passes through

Aperture - how large the passage of light

Mixing the amount of each is an art of light.  It is like your playing with light using your camera.

Keep on shooting.