To help prepare you for the marathon, Vancouver Photo Workshops instructor and 2011 12×12 judge Syx Langemann offers up a 6-part series of tips and tricks to get you through Saturday August 6th.
This is the third in our series, and this week we are going to talk about exposure. Exposure is the foundation from which any great photograph is constructed.
Once we have locked in the ISO of the film that we are using, the only two exposure tools available to us are the Aperture and the Shutter Speed. Let’s chat a little about each tool.
3. EXPOSURE 101
APERTURE refers to the size of the opening inside the lens. It controls the intensity of light that enters the camera. Technically, we can use this to help control the exposure values. By using a smaller hole in the lens we will need a longer shutter speed; the larger the hole in the lens, the shorter the shutter speed we need. Creatively speaking, aperture controls our Depth of Field. Depth of Field (DOF), relates to how much of the image is in focus from foreground to background. The lower the F-number, the larger the hole in the lens, therefore the shallower the DOF.
SHUTTER SPEED refers to how quickly the curtains open and close – how long the film is exposed to light. Based upon the ISO, the aperture and shutter speed are balanced to make a correct exposure. Shutter speed creatively controls motion in our picture. If the shutter speed moves fast it can stop motion, but this will require the correct aperture value to make a correct exposure. If the shutter moves slowly, the aperture can be ‘closed down’ (the F-number moved up) to correct the exposure.
When you are shooting your camera on a Program or Automatic mode, the camera is basing the exposure on the reflected light in the scene. It comes to the ‘best’ exposure value based upon an average grey to ensure the photograph is not over or under-exposed.
Our job is to balance the aperture and the shutter speed to get the picture we want, both in exposure value and in creative outcome. As long as we balance the numbers so that we can see a ‘0’ or ‘neutral’ exposure within the viewfinder, then we should have the correct exposure. However, we need to be aware of the combination of numbers that we are using to ensure that our photos are creatively successful. Again remember that a correct exposure is based upon an 18% grey. So as long as your scene contains both light and dark values, the camera should be judging the scene correctly. Look for this in your view finder:
By adjusting the aperture and the shutter speed, we will eventually come to a middle ground where the exposure should be correct.
So try this (you don’t even need to shoot the camera): Just move the camera around a scene from dark tones to light tones and watch your meter move. Then try to balance out the aperture and the shutter speed numbers so that the meter in your view finder is at ‘0.’ Then mentally trip your shutter. That should be a correctly exposed photograph.
Next time we will discuss a more advanced way of thinking about your exposure, but practice up, cause Tip #4 requires complete understanding of this one. See you next week.
Have a question or comment? Leave us a note below.
Click back next week when Syx shares Tip #4. You won’t wanna miss it!
Known for his Classically Twisted Nudes that push the viewer to discover new views of beauty, Syx Langemann has been photographing his own unique world since 1993 and can be found at Vancouver Photo Workshops teaching students how to capture theirs.
Syx is also one of the judges of the 2011 12×12 Vancouver Photo Marathon.