How to use exposure bracketing on your Canon DSLR
Getting exposure right is one of the biggest challenges you’ll face when shooting landscapes. Often, you’ll find that the ideal exposure times for the sky and foreground will differ by two to three stops. You can use a graduated ND filter to balance the exposure, but this means having to haul around filters and holders. Your Canon DSLR’s exposure bracketing function offers a nice compromise that lets you capture all the detail in your high-contrast scenes.
In-camera exposure bracketing enables you to expose correctly for each area of the image. Most Canon DSLRs enable you to select three (or more) exposure values for three exposures. The difference can usually be between one and three stops in one-third increments.
Once primed, the sequence is shot with one image under-exposed by a stop, one correctly exposed and one over-exposed by a stop.
So, for instance, if you were to expose a landscape for 1/250 sec at f/16, setting the bracketed exposures at one stop faster and slower, then the bracketed shots would be exposed for 1/500 sec and 1/125 sec.
This sequence will capture the full detail in the scene and can then be blended in Photoshop. Here’s how to set up your Canon DSLR to shoot bracketed shots for perfect exposures.
How to set up and use exposure bracketing
Set your camera to aperture priority mode, choose an aperture of f/16 and set the ISO to 100. Set the metering mode to centre-weighted. Take an exposure reading for the sky by making a note of the shutter speed, then take a reading for the foreground and shadow areas.
Use a tripod
The only aspect of the image that will change in each shot is the length of the exposure, so a tripod is essential. Attach your camera and compose the shot. To help beat camera shake, use a remote shutter release (or self-timer) and lock the mirror up (see your manual).
Switch to bracketing
Set the camera to take bracketed exposures. Refer to the notes you took earlier and choose an appropriate exposure range for the sequence. For instance, if your foreground reading is 1/250 sec and your sky is 1/1000 sec, then you would set the bracketing to +/- 2.
Check the histogram
After taking the sequence, read your histogram to check the over-exposed frame and ensure there are no clipped shadows, then examine the under-exposed image for burnt-out highlights. If either is clipped or too dark or bright, adjust the bracket by half a stop, then reshoot and recheck your images.
This entry was posted on Thursday, October 4th, 2012 at 6:00 am and is filed under Landscapes, Photography Tutorials. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a comment. Pinging is currently not allowed.