Exposure bracketing is on most cameras but it can seem like a complicated photographic technique to use.
However, it is relatively simple to do and edit afterwards!
What do you need?
A tripod/release cable
When might I use it?
It's a useful technique whenever there is a challenging scene with low light levels - ie indoors or a very contrast scene outdoors in strong light. It can also be handy for backlit subjects.
It is also a good approach if you don't feel you have time to fiddle with settings but want to be sure you've got the shot - a kind of guarantee, if you like.
How does it work?
In simple terms instead of just taking the one shot the camera ascertains is 'correct' - ie the middle of the exposure scale (0) - you take two more shots - one over exposed (+value) and one underexposed (- value).
How do I do it?
Find out where the Auto bracketing feature is on your camera - this may be a button (BKT or AEB) on the camera or it may be found within your shooting menu
If you don't have Auto Bracketing on your camera then you can still do this by using the Exposure Compensation tool - you'll just have to dial in the settings manually
Once open you can select how far along the exposure scale you want the over and under exposed shots to be set
Unlike using Exposure Compensation, where you would usually select a small adjustment, here you probably need to use at least +/- 1. This will guarantee you get the shadows and highlights properly exposed for your image. The middle exposure will usually get the midtones correct
Once set up your camera may take the three shots with one depression of the shutter or you may have to fire the camera 3 times
If you are just looking to 'hedge your bets' you won't need a tripod to capture the bracketed exposures. You will just be able to choose the 'best image afterwards and edit. If you shoot Raw you will have more adjustments possible in the edit process.
If, however, you are looking to create an HDR style image or plan to merge them to get the best result afterwards you need a tripod to make sure your 3 images are all identical otherwise the software won't be able to merge them effectively. Use a remote release to fire the shutter to make sure you don't move the camera in the process.
You may, of course, discover that one of the bracketed images works really well even if you shot them in order to merge them later. I sometimes find that the HDR function gives a slightly unreal look to the result - great if that's what you are after but not always.
NB: The resulting merged images can be massive in terms of size so make sure you have enough room to store theses big files as well as a computer that can handle processing them!
There are a few different ways to edit your images:
1. If you have just one image (the best of your three) then you can edit as usual paying attention to adjusting the highlights and/or shadows (depending on which exposure you chose) to create a balanced exposure
2. Merge the three images using the HDR merge tool - most photo editing software has this function and it really is a one click process. I do suggest that once the software has done it's thing that you tweak the results further - you may find you want to tone down the look of the merged image
3. Using Photoshop (or any software that allows you to edit using layers). You place the photos in a 'stack' and then combine them using the tools to either add or remove the elements. A longer process and which requires a little more skill and practice
NB my workflow means that I merge the images first and then correct any exposure issues, white balance etc.
Using a smartphone?
You can still bracket using your phone by adjusting the exposure with each shot - most smartphone cameras have a form of exposure compensation on them
Use the HDR function on the camera
Use HDR processing in apps such as Snapseed which mimics the results you get with bracketed exposures