PHASE 3: ALIGNING THE PANORAMA, STENCILS, AND HOTSPOTS
If you've shot with a carefully-leveled panoramic rig on a tripod, you may be able to align your image using the Auto Align function. However, I prefer using the manual Align option, where you draw two vertical lines next to buildings, poles, trees, or other objects you know are vertical. Stitcher then recalibrates the horizontal alignment of the scene, using the two vertical lines as reference points. Or you can draw one horizontal line to do the same along the other axis
The third phase also offers a Stencil mode, where subjects that moved in the original scene captures (and, therefore, appear in more than one image) can be removed from one or more frames. Yes, this is like using layer masks in Photoshop. In the Stencil mode, you select a frame and then draw a polygon around whatever you would like to have masked out. When Stitcher combines frames in the final rendering, the stenciled areas are ignored and image data is gathered from the unstenciled portions of other frames. Imagine shooting a street scene where the same person happens to appear in two spots of the panorama. You simply stencil her out in one frame, and -- voila! -- upon rendering she appears in only one location.
Phase three also offers you the opportunity to add hotspots for QuickTime VR movies. When hotspots are placed in panoramas, viewers can click on that portion of the image in order to follow a predefined URL, often an entrance to another panorama. Realtors, for example, use hotspots in their virtual tours of houses so that customers can navigate from room to room. Defining hotspots is as simple as stenciling. You just draw polygons, define the URLs associated with the hotspots, and create captions that appear at the bottom of the QuickTime viewer. Handily, on mouse rollover, the QuickTime VR navigator arrow changes to a hand to indicate a hotspot jump-to zone.
PHASE 4: EQUALIZING TONALITIES WITHIN THE PANORAMA
Light intensities and color may vary from image to image, sometimes due to properties of your equipment and sometimes due to changing conditions at a scene. Whatever the case, Stitcher blends each image with the next, equalizing them so that you don't see lines where they overlap. This is done quickly and automatically. This really goes a long way towards making your panoramas look slick, professional, and publishable.
PHASE 5: RENDERING THE PANORAMA INTO FINAL OUTPUT FORM
The last step in the Stitcher process is the most important. Here you determine what the final output will look like. Your options include a variety of panorama formats as well as producing movies. First of all, you can convert your stitched images by "rendering" them into cylindrical, cubic, and spherical images as well as flat "snapshots." Most interactive panoramas, such as QuickTime virtual tours, either simulate being inside a cylinder or an entire sphere. Cubic projections are used in more limited applications, such as creating 3D backgrounds. Cylindrical, cubic, and spherical images may be output for third-party players, namely QuickTime VR and Pure Player formats. Snapshots are standard, two-dimensional files that look like regular photographs and are suitable for printing.
The movie option allows you to produce .mov and .avi files, created as you direct movement within the panorama. For example, you can set a "key point" with a wide view, zoom in and set a second key point, pan left while zoomed and set the third key point, and zoom back out to set a final key point. Stitcher then processes the panning and zooming movements to produce a file that looks as if you were on location with a video camera. It's really quite cool and very easy to produce.
Here are a few pointers about Stitcher 5.6:
• As you progress through the five phases, the tonalities on the screen may not match exactly and the image may seem overly pixelated. This is normal, as the 3D projection of your panorama is a "draft," only approximating the final output. But, don't worry, the final output image will be rendered with much greater precision.
• If your final output format will be a "snapshot," i.e., a 2D image (as opposed to, say, a cylindrical output for a QuickTime VR movie), after loading your images you may need to select Edit > Properties and change the focal length to "Flat" if you used a long lens (e.g., 200mm or greater). The flat stitch is intended for when the camera or subject moves parallel relative to the other -- e.g., moving a document under a camera on a copy stand -- but, in my experience, panoramas shot from one location using longer lenses also may require the "Flat" focal length setting.
• The number of images you stitch is really only limited by your time shooting and how much memory and speed your computer has. I recently photographed fall foliage from a hilltop, creating a panorama of colorful tree tops using a 300 mm lens and stitching together 36 vertical images for one very l-o-o-o-o-o-o-o-n-g panorama ! Even with much overlap, the image is approximately 6.5 times longer than it is high, or a 1:6.5 aspect ratio!
• You may want to play with the Equalization Factor setting (Edit > Preferences > Rendering), experimenting with different values between 0 and 1. While the default is .7, a value that often will blend tonalities and colors well, you may find some images become overexposed. If so, try lowering the Equalization Factor and comparing rendered results.
• If you are in a special mode, e.g., Stencil or manual Align, exiting the function requires that you click the same icon you used to enter the mode. For example, you click on the manual Align, and the background turns blue to indicate the special function. After drawing two vertical lines, the panorama adjusts to the two reference lines. You then need to click the icon again to exit this mode.
• Some option windows, such as Properties, do not have an "Apply" or "OK" button, causing you to have to click the "x" in the corner to close them. While you might think that any values you changed would be lost, this is not the case. RealViz would do well to add "OK" or "Apply" buttons in places when they make their next iteration of Stitcher.
• The Preferences Dialog box allows for changing many parameters, such as workspace colors, preview options, and memory management. Although I found most of Stitcher 5.6's defaults to be quite good, I did change the thumbnail magnification setting. Go to Edit > Preferences > Thumbnails and set the "Thumbnail zoom" to "small." Otherwise, the images in the strip get larger as you mouse over them, which I found to be quite distracting.
• While it is possible to shoot panoramas handheld, the best results come from using a tripod and a specialized panoramic head, which will allow you to pivot the lens horizontally -- and with some rigs vertically, too -- around the lens's nodal point. This eliminates parallax from one image to the next. The Stitcher manual does a nice job of describing best shooting techniques.
• Speaking of the manual, it's good and bad. It's 146 pages long and has lots of information. Unfortunately, in many places key steps are mentioned too briefly and in others important information is completely left out. To fully explain all operations of Stitcher 5.6 would require a manual twice as long.
• Every performance machine has its hiccups, and my PC version of Stitcher 5.6 Unlimited DS is no exception. Occasional glitches, especially with movie production, sometimes slowed this otherwise dream-like 3D ride.
• Final panoramas rendered by Stitcher 5.6 are seamless; you really can't tell where any of the frames overlapped. Moreover, Stitcher 5.6 handles complex patterns with aplomb. In short, Stitcher 5.6 is by far best stitching program I've ever used.
• While Stitcher 5.6 offers a couple of user-selectable image adjustments, namely exposure and sharpening, I prefer to use PhotoShop to fine tune photographs before stitching.
• Stitcher 5.6 can handle most RAW formats, along with 32-bit HDR files.