Much like how carrots, celery, and onions are the three main ingredients that make up the definitive Holy Trinity of French cuisine, three key technical elements in the world of photography come together to make up the quality of a photographic image.  The trio includes ISO, shutter speed, and aperture.

ISO     Film Speed (sensitivity to light)

The general rule is the higher the ISO number, the more sensitive the camera is to the light. As the ISO number decreases, the better the color saturation, separation of tones, and sharpness.

As an example, a 50 ISO color film is 300% more saturated in color than reality for reds/yellows and 150% more saturated for blues/greens. On the other hand, a 1000 ISO color film is 25% less saturated than reality for reds/yellows and 40-50% less saturated for blues/greens. A 50 ISO 11″x14″ print wil be sharper than a 400 ISO 8″x10″ print.

Note that results are worse in digital than in film.  A 1600 ISO film print is equal to an 800 ISO print in digital.  (Digital is usually one level lower in ISO compared to film.)

Our goal is to always try to shoot at 100 ISO… never go above 400 ISO!

Shutter Speed     How long are we going to let in the light?

The shutter speed defines the exposure time and is measured in seconds. 

Note that the LCD monitor on most digital cameras displays the shutter speed as a fraction.  As an example, ”0″5” would indicate 0.5 seconds and “15″” would indicate a 15-second exposure.

Aperture/(F-Stop)     How much light are we going to let in?

The aperture is the opening through which the light comes in.  The diameter of the aperture opening is measured using a standard F-Stop scale.   

As a general rule, the larger the F-Stop number, the smaller the aperture opening.  A stop is simply a unit quantity used to define the ratio of light, with an increase in one stop corresponding to the aperture receiving only half of the light.  On the other hand, a decrease in one stop would imply the aperture letting in twice as much light.

Note that the range of apertures available will differ depending on the lens.  The maximum aperture opening is usually labeled on the front edge of the lens.  For instance, my 50mm lens opens up to F1.8 and is labeled as “1:1.8“.

Ever notice how most parents of first-generation Asian Americans all have this notion that their children were born with prodigious talent and would someday grow up to become world-famous concert pianists? My parents were definitely no exception. My sister and I both started playing the piano at a very young age, but it wasn’t until after I left home for college did I really learn to enjoy the art. I suppose it was because growing up I was forced to practice every day after school and instead of spending the weekends watching Saturday morning cartoons or playing in the park with friends, I was at my piano lessons with Mrs. Pfinning. As a small kid, I remember feeling even smaller every time I walked into her grand old country-style house. She had a quaint studio room especially dedicated for her lessons complete with a grand piano, an electric organ, a music stand for her violinists and an extravagant chandelier hanging from the ceiling. Off to the corner was a large, comfy, velvet armchair where I would sit to wait for my sister to finish her lessons before it would be my turn. Next to the armchair was a magazine stand filled with random children’s books and books on inspiration. One of my favorites was this little book entitled, All I Really Need to Know, I learned in Kindergarten.

I suppose in a way, I believe that it’s true… you learn the basics on life and human interaction in kindergarten to help you succeed in this world. According to the author, what you learn in kindergarten can be summarized into 16 major points and that is all you need to know on how to live, how to be and what to do in life. Fortunately, for us in the photography world, there are only three basic concepts to learn before you graduate from kindergarten, and they are ISO, shutter speed, and aperture. Just from these three concepts, we can derive exposure, depth of field, equivalency, and the metering system to finally arrive at the Sunny 16 Rule. And with that, you will be ready to head out and explore the world, fully-armed with camera in hand!