HDR Express will sit alongside the existing HDR Expose application in Unified's product lineup, and aims to simplify the process of creating high dynamic range images. Changes aren't limited to the user interface, however -- when compared to its sibling, HDR Express also brings improvements in the halo reduction algorithms it applies, and in its preview speed.

The program shares a similar user interface layout to that from Expose, retaining the same dark gray color scheme, tabs for each open HDR image, and side panel that groups most interface elements at the right-hand side of the screen. HDR Express also carries over the optional startup menu that prompts the user to open an existing image, or create a new one, enabled or disabled from the preferences dialog. Immediately upon creating or opening an HDR image, a couple of changes are notable, though. Helping beginners to appreciate the range of brightness available in a particular HDR scene, Express briefly shows an animation that ramps the brightness up over a period of a couple of seconds, showing available detail from the shadows right up to the highlights. This preview can be disabled if desired, and the animation can also be triggered manually courtesy of a play button beneath the histogram.

The histogram itself is quite similar to that in Expose, and offers a visual reference for the distribution of brightness in the current image or HDR merge, with a highlighted area called the Screen Zone indicating that range of brightness values that can currently be seen on the monitor. Beneath the Brightness histogram is a scale showing the exposure value of any particular point on the histogram, and beneath this there's a display of the RGB and BCH (brightness, chroma, hue) values for the specific area of the image which is currently beneath the mouse pointer. These tools together make it very easy to tell whether your exposure is correct, and to see whether there is further highlight or shadow detail available to restore to the image. Two new buttons at the top corners of the histogram panel allow the user to enable a clipping warning that fills clipped highlights with a red indication, while clipped shadows are shown with a blue fill.

A new preset panel spans the bottom of the screen, providing access to a new ease-of-use feature in Express -- the ability to render an HDR scene simply and with just a couple of mouse clicks on presets that provide the visual style you're seeking. First, the user selects from one of five tone-mapping presets that biases the overall exposure to save highlight or shadow detail, or somewhere in between. Once the tone-mapping preset is applied, you can then select from a variety of style presets that define the overall look of the rendered HDR image. Each preset has a user-friendly name, such as "Grunge," or "Soft & Cold," and is accompanied by a small preview thumbnail demonstrating the effect with your current image. In the tools panel at right, the selection of sliders available in HDR Express has been pared down to a bare minimum, reducing clutter and complexity significantly, while retaining a good degree of control. HDR Express offers controls for brightness, highlights, shadows, black point, contrast, saturation, warmth, and tint, and also retains the eye dropper tool which allows white balance to be adjusted from a neutral area in the scene.

As both tone-mapping and style presets are applied, the sliders in the tools panel are updated to reflect the style applied, and if you prefer to head straight into editing an HDR image manually, it's possible to start adjusting the sliders at any point. For example, you can select a tone-mapping preset and then begin tweaking the sliders without choosing a style preset, and you can likewise skip the tone-mapping preset if you'd prefer to adjust all sliders manually. (If that's the case, you can also disable the presets panel altogether, to recoup some screen real estate.) New users will most likely start from the foundation of an existing preset, though, and then tweak the sliders to refine the result. Helpfully, if you want to save your adjustments for future recall on the same or other HDR scenes, you can save your own style preset, and select which slider positions should be remembered for each preset. As sliders are adjusted, their effect is previewed on the image as soon as they're released. Making HDR Express feel rather snappier and more responsive, especially when used on more modestly powered computers, the engine driving the preview image will now intelligently render only the area of the preview that's currently visible, so if you're zoomed in on a particular detail in the scene, the whole preview needn't be rendered for every little adjustment.

Like its sibling, HDR Express not only merges multiple images into a single 32-bit image, but remains in this 32-bit color space for all image processing, unlike some applications which revert to 16-bit processing after the initial 32-bit merge. The algorithms used to merge images are largely similar to those in HDR Expose, but Express includes a new halo elimination algorithm which is not only faster, but removes the need to adjust strength manually. HDR Express retains the deghosting control from Expose, which operates in one of three modes -- Natural (which smooths areas of movement such as flowing water), Sharp Edge mode (which attempts to retain desirable detail such as moving people or cars), or Smooth Edge (which tries to perform a balance between the previous two approaches).

Unified Color's HDR Express is available immediately, with list pricing set at US$99, while HDR Expose will remain available at its current $149 price point. Providing an added incentive to photographers considering purchasing the software, HDR Express will be available through the end of December at a discounted price of $85. A free 30-day trial is available for both HDR Express and HDR Expose, and provides the full feature set with no watermarking or other limitations during the trial period. Unified Color's HDR Express is available for both Windows (XP, Vista, 7) and Macintosh (OS X 10.5 or 10.6) systems. As with HDR Expose, the newly released HDR Express can also function as a plugin for both Adobe Photoshop Lightroom and Apple Aperture, in addition to operating as a standalone application.