​The EXPOSURE TRIANGLE
 ISO, Aperture, Shutter Speed
Manual Mode

ISO:

  • ISO is the third and final element to how your camera captures light to get its exposure.  Remember, Shutter Speed (how long the camera captures light) + Aperture (how much light – how big the “hole” opening is in the lens)+ ISO (how sensitive the camera is to light)= Exposure (the total amount of light used to create your image).
  • Controlling ISO is usually done creatively more for the purpose of helping either the Shutter Speed or Aperture, or both.  By itself ISO doesn’t have much creative qualities other than to introduce “noise” at higher ISO settings (which as mentioned before, can be kinda cool at times.)
  • Play with your camera to see at what point you start noticing noise in your images.  There are ways in many editing software programs to help reduce or clean up noise in photos, so even if you have to shoot at a higher ISO than you’d like, sometimes you can still get fairly clean image after editing. A “noisy” image is better than no image or a super underexposed (dark) image.

Aperture:


​What is ISO on your camera?
  • ISO refers to how sensitive your camera is to light. Originally this referred to the film, but with digital cameras, the ISO sensitivity is in reference to the camera’s sensor.
  • Basically, the more sensitive your camera is to light, the higher the ISO number, the more possible it is to shoot in low light situations.
  • Higher ISO number = higher sensitivity to light = better ability to shoot in low light

How is ISO measured?
  • ISO is measured by numbers that are based on an older film standard.  For example, film comes in different speeds such as 100, 200, 400, 800 and above. Recommended film speeds for daylight or bright, outdoor situations usually calls for 100-200 speed film. Darker situations, indoor shots or sports shots called for the higher speed films.
  • The same number now refers to the the sensors on digital cameras, which are measured in the same numbers.
  • The lower the number, the less sensitive, the higher the number, the more sensitive the camera’s sensor will be.  The numbers can range anywhere from 50 to 6400 and beyond, depending on the camera.
  • So, if you’re shooting in lower light situations and your pictures come out too dark, you can increase your ISO number to make it more sensitive to light, making the photographs brighter.
How do you control ISO?
  • Almost all cameras will allow you to manually adjust your ISO setting, however many also offer an Auto-ISO mode, or something named similarly.  Usually in this mode, you are able to tell the camera the parameters you want it to stay in (highest ISO, lowest shutter speed.) Check your manual or search online for your individual camera on how to do this.  Every camera varies.
Example of ISO light sensitivity: One way to control your exposure is by controlling the ISO












How is Aperture measured?
  • Aperture is measured in the size of the “hole” opening in the lens
  • Aperture is measured in a measurement called “f-stops”
  • The size of the aperture hole opening determines the f-stop number
  • The BIGGER the aperture hole opening, the MORE light comes in, which gives a SMALLER f-stop number.
    • The smaller f-stop numbers (such as 1.4, 2.8) let more light into the camera, and these numbers are considered “FAST”
    • So when you hear of terms like “fast lens”, “fast aperture”, “fast f-stop”, just know that means the lens is able to open up WIDE and letting more light coming in.
    • More confusing terms you will hear when describing the big hole opening: “Stop down your f-stop”, “wide aperture”, “open up your f-stop”. All that means is to let more light into the camera by opening up the aperture hole opening, which you do by making the number smaller.
  • The SMALLER the aperture hole opening, the LESS light comes in, which gives a BIGGER f-stop number
    • The bigger f-stop numbers (such as 6 or bigger) let less light into the camera, and these numbers are considered “SLOW”
    • So when you hear of terms like “slow lens”, “slow aperture”, “slow f-stop”, just know that means the lens hole is SMALLER and give you less light coming in.
    • More confusing terms you will hear when describing the smaller hole opening” “Stop up your f-stop”, “small aperture”, ” close your f-stop”. All that means is to let less light into the camera by closing up the aperture hole opening, which you do by making the number bigger.

Shutter Speed:

Picture
How is Shutter Speed measured?
  • Shutter speed is measured in seconds, or fractions of a second, which will look like these examples:
    • 1/80 – means one eightieth of a second. Most cameras will just show  the number “80”
    • 1/100 – means one one-hundredth of a second. Most cameras will just show the number “100”
    • 1/400- means one four-hundredth of a second. Most cameras will just show the number “400”
    • 1″ – means one full second.  Most cameras will show ” 1″ “
    • Shutter speed can have bigger and smaller numbers, but you got the point, right?
    • Because your camera is usually only showing the bottom part of the fraction, the BIGGER the number, the FASTER the shutter speed, the LESS light enters your camera. This means that your exposure is SHORTER, the image will be DARKER. Imagine this: the faster the shutter opens and closes, then obviously, less light comes through. If you stand in front of your window and open/close the window shutters fast, you have less light entering the room.
    • Fast = less light = big number.
    • The  SMALLER the number, THE SLOWER THE SHUTTER SPEED, the MORE light enters your camera. This means that your exposure is LONGER, the image will be BRIGHTER. Imagine this: the slower the shutter opens and closes, then obviously, the more light comes through. So, if you stand in front of your window and open/close the window shutters slowly, you have more light entering the room.
    • Slow = more light = small number.