HDR, BRACKETED EXPOSURE, AND AEB?
In this quick tutorial I will explain what these three terms are and how I use them.
HDR stands for High Dynamic Range, and it is a technique in which you merge several differently exposed photographs together to create an image with a more complete dynamic range similar to what our human eye’s see. The first time I heard about HDR was from Paul Debevec at Siggraph in 2004. He had a great lecture on image based lighting and he showcased the Parthenon recreated from 3d scans.
Bracketed Exposure is a term referring to a set or series of the same image each one taken at a different light stop, in short the first image will normally be dark (under exposed), the second will be "technically" spot on and the third shot will be bright (over exposed).
Auto Exposure Bracketing (AEB) is a camera setting in which it takes a series of photos all with different exposure values, all automated so you don’t have to manually make changes to get your set of Bracketed Exposures.
How to Set Auto Exposure Bracketing (AEB) on the Canon DSLR
On the Camera, which is my current DSLR...
1. Go into the menu, if you forget where the button is its still located on the back of the camera to the left of the screen.
2. Select the Exposure Compensation / Auto Exposure Bracketing (AEB) option.
3. Press the set button and using the small wheel, location on top of the camera, move the EV indicators apart until you have them at either side of the center pointing at number 2. This will give you an exposure value of -2, 0, +2 for you bracketed shots.
4. Press the set button to save the option, and then use the menu key to back out of the AEB menu.
Your camera is now setup to take a set of three shots, each one with a different exposure. Again, note that due to the limitation of the Canon 7D you can only take 3 auto bracketed shots at once.
5. Set your camera on a tripod and change the drive mode to continuous. Pre-focus and compose the shot. Using the self-timer, a remote or my choice an app like triggertrap, fire off your bracketed shots.
You can now simply load the shots into your chosen software package and create your HDR photos. I first bring them into Photomatix and then save it out as a 32 bit tiff. I then open the TIFF in Photoshop and use the camera raw settings to tweak the image.