course notes

Positive compensation: use when the background is brighter than the main subject (i.e. to let in more light to compensate for incorrect underexposure) Negative compensation: use when the background is darker than the main subject (i.e. to reduce the amount of light, to compensate for incorrect overexposure) CARE: Exposure compensation is usually not reset automatically when the camera is turned off. Ensure you set back to ‘0’ before turning the camera off.

Exposure Bracketing Useful in complex lighting conditions, to ensure that one of three shots is correctly exposed.

The camera will produce three shots: with each shot, the camera varies exposure by fixed increments (eg one at the exposure automatically selected by the camera, then one at a positive exposure increment and one at a negative exposure increment) The default size of the exposure increments will usually be 1/3 stop can be varied using the menu on your camera. Some camera’s allow to custom tailor the bracketing on the positive or negative scale.

Depending on the camera, you may only need to press the shutter once to produce the three bracketed images. For others, you may need to press the shutter three times, with the camera automatically adjusting the exposure for each shot.

Flash sync modes Front curtain: Most commonly used. Shutter speed will be automatically set to values in a given range, depending on the camera.

Red eye reduction: Red-eye reduction lamp flashes before main flash resulting on contraction of the subjects pupils.

NB: This causes a slight delay before the picture is taken (up to about a second or so) so is not recommended in situations where quick shutter response is required.

Slow sync: Flash can be combined with slow shutter speeds (eg to capture both background and subject in low light/at night). Use a tripod or support to avoid camera shake.

Rear/2nd Curtain synch flash The flash fires just before the shutter closes, rather than at the start of the exposure. Use to capture both subject and background without blur, in low light situations.

Can also be used for special effects such as capturing light streams behind moving subjects. Use of a tripod recommended to avoid camera shake Flash Range Range = the area reached covered by the flash output The range varies according to light sensitivity (ISO) the aperture & sync speed of flash.

The aperture widens (i.e. the smaller the f-stop number) the flash range increases.

As ISO is increased (e.g. from 400 to 800) the flash range increases.

The built-in flash will have a minimum ‘distance to subject’ below which it cannot be used. It will also often not be possible to use the built-in flash with macro lenses as you are too close to subject. However you can direct the light with a small reflector.