This is part 2 of my article on taking HDR images with the Nikon D7000. This part explains how to take the actual shots. An introduction to HDR can be found here: HDR with the Nikon D7000 — part 1.
HDR — when to use it?
When does it make sense to take a HDR image? The answer is: when there is a high dynamic range to capture — very bright and very dark areas, and you do not want to lose any of them. An example would be the last rays of sunlight coming through the leaves in a dark forest. Or you take a picture under a small bridge, and you want the structure of the stones under the dark bridge AND the brightly lit scenery in the background to be exposed similarly bright. Or consider a dark church, where some interesting parts like large paintings are lit by strong lights. People also often use HDR for sunsets and stuff like that. Most people just use it because they think it is cool, and searching google for HDR images returns many pictures that I personally find very ugly (and I can tell which button in Photomatix Pro all of them clicked to create that ugly look), but that’s a matter of taste I guess. So let’s get started.
Taking the shots
There are some basic things you should consider when taking HDR shots:
- Use a tripod. Some reasons: You are taking several shots (often 3) in quick succession to merge them to a single HDR image later. If you don’t use a tripod, the frame won’t be the same for all 3 images. Also, you expose them differently, and one of them (the one with the longest exposure time) may get blurred even though the other 2 came out fine. You can try to compensate for both in software later of course, but it is work and you will lose quality.
- Avoid moving objects in the frame. It takes time to take 3 images. Fast moving objects may have changed their location in between the shots. Fixing this can be quite a bit of work.
Finding the correct buttons on the D7000
The process of taking HDR shots is called exposure bracketing. Bracketing roughly means you take several shots with different settings in difficult situations, bracketing the setting you consider best. You can bracket various things, not only exposure. White balance, for example, AD-lighting or flash. But what we are interested in for HDR is exposure bracketing. The first thing you need to do is to find the bracketing (BKT) button. Let’s have a look at the BKT button of the Nikon D7000 and the Nikon D800:
Camera setup — taking the photos
Once your camera is on the tripod and you got a suitable scene in front of the lense (or maybe better before this, in a dry-run session), it’s time to press the correct buttons. Here is what you need to do (this is also explained in detail on page 109 of the english Nikon D7000 manual):
- Prepare camera: Ensure that the bracketing mode is set to AE bracketing (not flash, white balance, or something else): In the Nikon D7000 menu, navigate to Custom Settings e5 and ensure that AE only is selected.
- Set fixed ISO value, and mode to A or M (manual): You can take a HDR series with ISO auto and in other modes than A or M, but I want that the setting that gets changed in order to reach the different exposures is shutter speed. In other modes (P or S) and with auto-ISO active, the camera changes ISO or aperture also. (To set a fixed ISO, go to [MENU] => Shooting menu => ISO sensitivity settings => auto ISO control => off with the Nikon D7000.)
- Select the number of shots: You usually want the maximum of 3 shots: one photo with the currently set value, one underexposed and one overexposed. To do this, while holding the BKT button, rotate the main dial (that is the wheel on the back of the camera, where your thumb is) and watch the control panel. The values change between +2F (set value and overexposed), -2F (set and underexposed) and 3F (set and both). Ensure that 3F is selected.
- Select the increment to use (in EV). This setting defines how much the exposures will differ between shots, and the best value depends on the scene you want to photograph (larger differences in light intensity means you need higher values). You can select valeus from 0.3 up tp 2.0 EV.
- Set the exposure: Set the exposure to something suitable for the scene. This is the medium value of the 3 shots.
- When you are done, leave BKT mode:
Note that for 3 exposures, you have to click the button 3 times. The D7000 will NOT take all three exposure with one click like with some point-and-shoot cameras. (You can get this behavior by using self-time mode though, e.g., to avoid the tiny shake from pressing the button.)
Do not forget this, it can be extremely annoying to have BKT mode active without noticing. To disable bracketing, just hold the BKT button and rotate the main dial and set the number of shots to 0F, the BKT icon will also disappear then.
That’s it, you now have a series of 3 shots from the same scene, which differ by the EV value you set (and by different shutter speed). Everything else, including ISO and aperture, is the same for all images. You can now process this image series and create a single HDR image out of them using tone mapping software like Luminance HDR (free), Photomatrix Pro, or other software. This will be explained in part 3 of this article series.
Here are 3 example shots: