Perfect Exposure

Course outline

• How to Measure and Set Exposure

  Cameras offer an increasingly sophisticated range of methods for getting the exposure in some way ‘correct’, but though the result is a wonderful choice, there’s also a chaotic array of methods and jargon. My job here is to cut through this nonsense, and my model is, as always, the way professionals like myself think and work. What average brightness means Highlight clipping & warning Basic camera metering: centre circle, spot and weighted Advanced camera metering: smart and predictive Auto metering modes Aperture priority Shutter priority Program Exposure compensation Manual metering Bracketing Check the histogram After the shot Live View Handheld meter & incident readings Grey card

• The Exposure Triangle

  There are three camera settings that each control the brightness of the image you capture—aperture, shutter speed and ISO—and this lets you choose a combination to get any particular exposure, hence the expression exposure triangle. Using it efficiently means knowing clearly what your priorities are for any shot. Apart from controlling the light, the aperture and shutter speed each do another job for the image. Aperture affects depth of field while shutter speed affects motion blur, and you may want less or more of either in any specific shooting situation. ISO raises the sensitivity when you need it, but the result is noise, which has no redeeming qualities, so this just increases the compromises you need to make when light levels are low. Balancing aperture, shutter speed and ISO Aperture = depth of field Shutter speed = freezing or blurring motion ISO = noise Using camera modes Auto ISO Know your limits Hand-holding speed Minimum shutter speeds for motion Minimum depth of field for a subject Your noise tolerance Deciding priorities

• The Twelve Exposure Situations

  Regardless of subject, there are just 12 basic lighting situations in photography, and each one needs a particular set of techniques. Become familiar with them and you will quickly be able to assign any scene in front of you to one of these—and know what technique to apply. Dynamic Range: Scene & Sensor Group 1: The Range Fits 1 average 2 bright 3 dark Group 2: Low Contrast (range fits easily) 4 average 5 bright 6 dark Group 3: High Contrast (over range) 7 no obvious dominant tone 8 large bright subject 9 small bright subject 10 edge-lighting 11 large dark subject 12 small dark subject

• Exposure and Style

  In the last two lessons we looked at finding the exposure that essentially best suits the situation. Now I want to move things on to the next level, which is to take all of this and temper it with judgment and creativity. In exposure, there is no wrong and there is no right. If you embrace this, you can start to experiment with different styles of imagery that go beyond the obvious and average. Like any artist, you then have to rely on your judgment. Style in exposure depends heavily on deciding what the most important tones are in the picture—and then choosing how you want them to appear. Key tones Memory tones Know what you want Light and bright High key Sombre Low key Shadow detail Silhouette Don’t obsess Decision workflow