Better (And Faster) Panoramic Images; Problem Panos Now Have A Solution Page 2

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Step 6.
Now return to Bridge and reselect the source files, this time substituting the masked pictures, for the originals in the sequence. Choose Tools>Photoshop>Photomerge and then select the same Layout option used to create the draft panorama in Step 2. The final result should be free from ghosting, but if some still persists, fine-tune the masks in your source images, and stitch again.

Top Tips For Creating Great Panoramas
1. Set Up For Quality

Though stitching utilities such as Photomerge are getting better at correcting for source images that are captured handheld, most panoramic professionals insist on using a tripod coupled with a special panoramic head to take their series of images. The tripod provides a stable and level base for the camera and the panoramic head contains regular click stops to suit the lens of the camera being used. Each stop is designed to provide optimum coverage for each frame, taking into account the required edge overlap. If you don’t have a special panoramic head try rotating the camera around the lens rather than pivoting around your body. Also if you are shooting handheld use longer focal lengths rather than wide angle lenses; this will help with stitching later.

2. Wait For It!
Timing is important when photographing the sequence of images. Objects that move in the frame or are positioned at the edges of one picture and not the next do cause stitching problems. If you want to save the time needed to mask the problem photos then try to time your capture sequence when the edge details at the overlapping sides of the frame are consistent.

3. Manual, Manual, Manual!
As the lighting conditions can change dramatically while capturing the sequence of images you need to make up a panorama, it is important that the camera’s exposure be set manually. Take readings from both the shadow and highlight areas of the scene before selecting an average exposure setting, or one that preserves important highlight or shadow detail. If the camera also has autofocus and auto white balance features these too should be adjusted manually. This will help to ensure consistency of color, focus and exposure throughout the whole of the picture sequence. Though the blending abilities of Photomerge remove the need for this level of control in a lot of images the best results will always be obtained if you take extra care in the shooting stages.

4. Be Consistent With Your Overlap
As you are capturing, ensure that the edges of sequential images are overlapping by between 10 and 40 percent. The exact number of images needed to complete the full circle will depend on the angle of view of the lens as well as the amount of overlap that you have used. Some cameras provide a special Panorama mode that ghosts the previous shot in the LCD screen so that you can line-up the next picture accurately. Professional VR heads ensure shooting consistency by placing “click stops” at regular points on the circumference of the head.

Auto-Align, Auto-Blend And Photomerge CS3
In the CS3 release of Photoshop, Photomerge has been completely updated to include both automatic and manual stitching workflows. Based on two new pieces of technology—Auto-Align and Auto-Blend—stitching can now occur either inside the Photomerge work space (now called the Interactive Layout), or via these two new options in the Edit menu. Auto–Align and Auto–Blend are generally applied individually to a multi-layered document whereas Photomerge itself is used for bringing together separate source files.

Photomerge can be started from the File menu (File>Automate>Photomerge), or via the Tools>Photoshop>Photomerge option in the Bridge file browser.

The latter approach allows the user to select suitable source pictures from within the browser before activating the feature. Next you will be presented with a new Photomerge dialog containing options for adding and removing source files, as well as five different stitching and blending or Layout options. They are:

Auto—aligns and blends source files automatically.

Perspective—deforms source files according to the perspective of the scene. This is a good option for panoramas containing 2-3 source files.

Cylindrical—designed for panoramas that cover a wide angle of view. This option automatically maps the results back to a cylindrical format rather than the bow-tie shape that is typical of the Perspective option.

Reposition Only—aligns the source files without distorting the pictures.

Interactive Layout—transfers the files to the Photomerge work space where individual source pictures can be manually adjusted within the Photomerge composition. This is the only non-auto option.

In most circumstances one of the auto options will easily position and stitch your pictures, but there will be occasions where one or more images will not stitch correctly. In these circumstances use the Interactive Layout option. This displays the Photomerge work space where individual pieces of the panorama can be moved or rotated using the tools from the toolbar on the left-hand side of the dialog. Reposition Only and Perspective options are set using the controls on the right. Photoshop constructs the panorama when the OK button is clicked.

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