| Taking photographs of a high contrast scene |

The shooting phase is essential for getting good results with Photomatix. To photograph a high contrast scene, you need to take several exposures in order to capture information in both the highlights and the shadows of the scene. The exposures taken will have to properly cover the dynamic range of the scene, especially the shadows.
The number of photos you need depends on the scene. It also depends on the Exposure Value (EV) spacing separating the photos. If you take them in one-EV steps (e.g., -1, 0, +1 EV), you will need more photos than if you take them in two-EV steps (e.g., -2, 0, +2 EV). We recommend shooting in two-EV steps whenever possible.
A spacing of two EVs between the images means that the exposure time of one photo will be four times higher or four times lower than the exposure time of the next exposure in the sequence. For instance, if the photo at the middle exposure is taken at 1/15 second, an EV-spacing of two means that the overexposed photo will be taken at 1/4 second and the underexposed one at 1/60 second.
High contrast scenes can be grouped into roughly two types depending on their dynamic range:
· | Medium dynamic range scene: Most landscapes and other types of outdoor scenes fall into this category. Three exposures taken in two-EV steps (i.e. -2, 0 +2 EV), or five exposures taken in one-EV steps, are usually sufficient for this type of scene.
· | High dynamic range scene: A typical example is the interior of a room with a view outside the window on a sunny day. You need to take at least five exposures in two-EV steps (or nine exposures in one-EV steps) to capture this type of scene, but you may need more. Taking the exposures manually is recommended in these cases.
The source photographs for HDR processing can be taken with digital or film-based cameras. The only requirement is that the exposure can be adjusted when taking pictures. If you use a film-based camera, you will need to scan the photographs into your computer before processing them.

Camera set up
1. | Set your camera to Aperture priority (A setting) so that only the shutter speed varies between the exposures.
2. | Select a low ISO (e.g., ISO 100 or lower).
3. | Turn the flash off. The flash may try to balance the exposure of all the images, when a range of exposures is the goal.
4. | Whenever possible, mount the camera on a tripod. Even though Photomatix Pro offers automatic alignment of hand-held photos, using a tripod is always better.
DSLR cameras and some compact digital cameras offer Automatic Exposure Bracketing (AEB). This enables you to automatically take three or more exposures in a row: one at the proper exposure, one or more underexposed, and one or more overexposed. Follow these steps if your camera offers AEB mode:
1. | Select the Continuous shooting mode on the camera's drive setting. Consult your camera manual for model-specific instructions for using this setting.
2. | Set the camera to Auto Exposure Bracketing (AEB)
3. | If possible, use the camera's self-timer setting, or a cable release to minimize camera shake.
4. | Set the exposure increment to +/- 2 for optimal exposure range. If your camera does not offer +/- 2 exposure increments, select the maximum possible. Consult the camera manual for model-specific instructions for choosing this setting.

Selecting the exposures
To get good results with HDR processing, your capture sequence must include photos that correctly expose highlights and photos that correctly expose shadows. The latter is especially important to avoid noise showing in the processed HDR image.
In the lightest photo of the sequence, the darkest shadows should be at least in the mid-tones. You can check that with your camera's histogram preview in playback mode. In your most overexposed photo, the left part of the histogram should be empty until 1/3rd of the histogram's width. If this is not the case, you will have to add one or more photos taken with longer exposure times. Another option is to re-shoot the exposure sequence with the normal exposure set one or more EVs higher if your most underexposed image in the exposure sequence was too dark. This is the case when the histogram of your darkest image is completely empty on the right half.
The number of exposures needed depends on the dynamic range of the scene, in addition to the exposure increment. For most outdoor scenes, three exposures taken at +/- 2 exposure increments will be sufficient, provided the scene does not include the sun. However, for the interior of a room with a bright view out the window, you will need at least five images taken with an exposure increment of +/- 2, or nine images taken with an exposure increment of +/- 1.
In scenes with extreme differences between light and dark details, you should change the exposures manually to ensure you capture a wide enough range to cover your scene.

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