Create HDR Brackets from One Raw Exposure
You can create brackets from a single Raw exposure and then use them to prepare a high dynamic range photograph by altering the exposure value (EV) in your Raw editor and saving the results. Here’s how to perform the procedure in Adobe Camera Raw:
Open the single Raw source image in Photoshop Elements or Photoshop to launch Adobe Camera Raw.
Adobe Camera Raw can’t be launched as a separate process. It automatically opens when you open or drop a Raw photo in Photoshop.
Make any necessary changes to the image.
You might want to carefully sharpen and tweak color temperature or white balance. The restrictions here are less stringent than editing separate brackets because this image serves as the master bracket.
Lower the exposure by –2.0 EV by adjusting the Exposure slider or entering –2.0 in the Exposure text box.
The Exposure slider is on the Basic tab, as shown in the figure, whose icon is a small, six-blade diaphragm (creating a lens aperture). Select the tab if you can’t see the Exposure slider.
This gives you the underexposed image, as seen in the top image in the series of photos. Notice the effect lowering the exposure has on the highlights. In this case, the sky and white shed have gone from close to being washed out to nicely exposed.
You can experiment with lowering the EV by smaller increments and creating more files if you like, but you should have a total range of at least +/–4.0 EV across your brackets.
Save the lower bracket as a new file.
It helps to use a file naming convention. For example, you can keep the original filename and append information at the end, such as the bracket number (DSC_1303-01.tif, DSC_1303-02.tif, DSC_1303-03.tif), add the Raw application you used (DSC_1303-acr-01.tif), or specify a preset (DSC_1303-noisereduction-01.tif).
For the highest quality, choose 16-bit TIFF. If space is a concern, choose 8-bit TIFF. You can choose JPEG if you like, but your HDR image may suffer from noise problems as a result.
Raise the exposure back to 0.0 EV by adjusting the Exposure slider or entering 0.0 in the Exposure text box.
This is your center, perfectly exposed bracket. (See the middle image in the series of photos.)
Save the middle bracket.
Choose the same format as the previous bracket. Remember to name this bracket something different than the first bracket. You can simply increment your own bracket number, as described in Step 4.
Raise the exposure to +2.0 EV by adjusting the Exposure slider or entering +2.0 in the Exposure text box.
Third time’s the charm. This is the overexposed bracket. (See the bottom image in the series of photos.) Notice that the other settings are the same. That’s pretty important.
Save the upper bracket.
Choose the same format as the previous brackets. Name appropriately, using the convention you’ve decided upon (see Step 4 for helpful guidance).
This figure illustrates the finalized HDR image that was created from the three bracketed images.