Controls 101

Explains the basic camera controls…not the full usage..that will be for the chapter on Photography Lessons 101

Basic Camera controls you will see on the

top deck of your camera:

  1. Program Setting: “P”
  2. Manual Setting: “M”
  3. Aperture Priority Setting: “A” (where you set the f/stop and the camera sets the shutter speed)
  4. Shutter Priority Setting: “S” (where you set the shutter, and the camera sets the f/stop)
  5. Auto Setting: “Green Square” or “Green Symbol”

Three other Camera Controls Related to Exposure

  • f/stop: this is a number that describes opening size of the Iris inside the lens. The # is a representation of a fraction. For example, f/2 = the focal length divided by 2. (Where f = the focal length). Say you have a 50mm lens set at f/8.  That would make the fraction 50/2. the REAL OPENING in MM would be 25mm in diameter. But, for now, just remember that the larger the number is, the smaller the iris opening is. It is a fraction! f/2 is a larger opening than f/8. The f/stop determines the “AMOUNT” of light that reaches the image sensor.
  • Shutter Speed: This is the number that determines “HOW LONG” your are going to expose the image sensor to the “AMOUNT” of light coming through the lens iris opening, (f/stop). These, again, are fractions. [I wish I would have studied fractions in HS-  ;-D ]. Examples in 1/3 steps “……..60, 80, 100, 125, 160, 200, 250, 320………” Examples in 1/2 steps” …….60, 125, 250, 500, 1000……”  Now, I said these are fractions. They are, fractions of a second. So, 60 = 1/60,  160 = 1/160,  250 = 1/250,  500 = 1/500 of a second. Now to add one more bit of knowledge that you may find useful.  If your camera uses 1/2 steps, than, you can remember that there is a logical scheme to those numbers. each number is progresion of 1/2 or 2x.
    • 1/60 is 1/2 of 1/30 in the “AMOUNT” of time the shutter is open.
    • 1/30 is 2x 1/60 in the “AMOUNT” of time the shutter is open.
  • ISO (Like The Film Speed setting on film cameras). Have a similar progression as shutter speeds and f/stops. (see a pattern here?) That is: ISO (ASA in old school terms), steps can be in 1/2 or 1/3 steps, depending on how you set up your camera. It looks like this. ISO 100, 125 160, 200, 250, 320, 400, 500, 640, 800, 1000, 1250, 1600 .

If we had every thing in 1/2 steps, the way it used to be expect for ISO settings, we could see the common relationship better:


ALL the  Below Combination’s are all EQUAL in the same exposure.

Click on image to see it bigger

f/2 @ 1/500 = f/2.8 @ 1/250 = f/4 @ 1/125 = f/5.6 @ 1/60.….and so on. So what just happened here? As I closed down the f/stop to the next smaller opening (f/2.8, the next larger number), the lens is letting in 1/2 the amount of light. So to achieve the same exposure as the earlier setting (f/2 @ 1/500), I will need to have the shutter stay open for 2x the earlier setting (1/500) to 1/250, which holds the shutter open twice as long as 1/500.

There are numerous other “Picture” symbols for specialized situations. These symbols vary from each maker. And basically make minor exposure adjustments in the f/ stop, shutter speed, and ISO settings. Some may also effect the flash and frame advance method (Single Exposure or Continuous exposure at 1.5x to over 5x per second).

What each mode does

  • “P”rogram mode: Sets the cameras f/stop & Shutter Speed. All you do is aim, focus and shoot. This is the most common camera setting. It allows you to concentrate on the image you want to capture, instead of being bothered with setting the exposure controls manually. Another benefit with using “P” mode, is that you will have a bit more control with some of the camera settings. Such as the ability to change the ISO setting, or change the Flash Exposure Compensation setting (FEC), for instance. (I’ll explain what the “FEC” settings are for in another section of this chapter).
  • “A”peture priority mode: Sets the camera shutter speed as you set the f/stop for the proper depth of field. This mode is very useful when you are taking photos of people. Especially for head shoots, and 3/4 shoots.  Another use is for wide angle lenses that can be used for Point & Shoot style candid photography. Here, you would set your lens at, lets say, f/11, and you can have all things in focus from 4 feet to INFINITY. I will explain this concept in Shutter Speeds & f/stops.
  • “S” hutter priority mode: Sets the Aperture or “f/stop” as you set the shutter speed to make sure you can stop any subject movement. This is very useful on sports photography, be it your child’s sporting event, or a pro sporting event.
  • “M”anual mode: You set the Shutter Speed AND the f/stop as you use the manual metering to obtain proper exposure. (consult your user manual for instructions on using “manual” exposure mode)
  • “Green” Auto Mode: Very basic auto mode. This mode will cripple some functions in your camera. Such as: Manual ISO setting, Continuous motor drive setting, manual metering pattern mode. This mode is like Program mode, but, without options available in “Program” mode. GREEN AUTO has: Auto ISO, Auto f/stop, Auto Shutter Speed. Auto White Balance.