The Photomerge™ command combines several photographs into one continuous image. For example, you can take five overlapping photographs of a city skyline, and then merge them into a panorama. The Photomerge command can assemble photos that are tiled horizontally as well as vertically.
Book excerpt: Panoramas made easy
To create Photomerge compositions, choose File > Automate > Photomerge and then choose your source files and then specify layout and blending options. Your option choice depends on how you photographed the panorama. For example, if you’ve photographed images for a 360 degree panorama, the Spherical layout option is recommended. This option stitches the images and transforms them as if they were mapped to the inside of a sphere, which simulates the experience of viewing a 360 degree panorama.
For a video overview of Photomerge, see www.adobe.com/go/vid0013.
Take pictures for Photomerge
Your source photographs play a large role in panoramic compositions. To avoid problems, follow these guidelines when taking pictures for use with Photomerge:
Overlap images sufficiently
Images should overlap by approximately 40%. If the overlap is less, Photomerge may not be able to automatically assemble the panorama. However, keep in mind that the images shouldn’t overlap too much. If images overlap by 70% or more, Photomerge may not be able to blend the images. Try to keep the individual photos at least somewhat distinct from each other.
Use one focal length
If you use a zoom lens, don’t change the focal length (zoom in or out) while taking your pictures.
Keep the camera level
Although Photomerge can process slight rotations between pictures, a tilt of more than a few degrees can result in errors when the panorama is assembled. Using a tripod with a rotating head helps maintain camera alignment and viewpoint.
Stay in the same position
Try not to change your position as you take a series of photographs, so that the pictures are from the same viewpoint. Using the optical viewfinder with the camera held close to the eye helps keep the viewpoint consistent. Or try using a tripod to keep the camera in the same place.
Avoid using distortion lenses
Distortion lenses can interfere with Photomerge. However, the Auto option adjusts for images taken with fish-eye lenses.
Maintain the same exposure
Avoid using the flash in some pictures and not in others. The blending features in Photomerge helps smooth out different exposures, but extreme differences make alignment difficult. Some digital cameras change exposure settings automatically as you take pictures, so you may need to check your camera settings to be sure that all the images have the same exposure.
Create a Photomerge composition
Choose File > Automate > Photomerge.
In Adobe® Bridge, choose Tools > Photoshop > Photomerge from the Bridge menu bar. Skip to step 5.
In Bridge, choosing the Photomerge command uses all images currently displayed in Bridge. If you only want specific images used, select them before choosing the Photomerge command.
For a video that shows the effect of each Layout option, see www.layersmagazine.com/photoshop-cs4-photomerge.html.
Photoshop analyzes the source images and applies either a Perspective, Cylindrical, and Spherical layout, depending on which produces a better photomerge.
Creates a consistent composition by designating one of the source images (by default, the middle image) as the reference image. The other images are then transformed (repositioned, stretched or skewed as necessary) so that overlapping content across layers is matched.
Reduces the “bow‑tie” distortion that can occur with the Perspective layout by displaying individual images as on an unfolded cylinder. Overlapping content across files is still matched. The reference image is placed at the center. Best suited for creating wide panoramas.Applying Cylindrical Mapping
Aligns and transforms the images as if they were for mapping the inside of a sphere. If you have taken a set of images that cover 360 degrees, use this for 360 degree panoramas. You might also use Spherical to produce nice panoramic results with other file sets.
Aligns the layers and matches overlapping content and transforms (rotate or scale) any of the source layers.
Blend Images Together
Finds the optimal borders between the images and create seams based on those borders, and to color match the images. With Blend Images Together turned off, a simple rectangular blend is performed. This may be preferable if you intend to retouch the blending masks by hand.
Removes and performs exposure compensation in images that have darkened edges caused by lens flaws or improper lens shading.
Photoshop creates one multi‑layer image from the source images, adding layer masks as needed to create optimal blending where the images overlap. You can edit the layer masks or add adjustment layers to further fine tune the different areas of the panorama.
To replace empty areas around image borders, use a content-aware fill. (See Content-aware, pattern, or history fills.)
Create 360-degree panoramas (Photoshop Extended)
Combine Photomerge with 3D features to create a 360-degree panorama. First, you stitch together the images to create a panorama; then you use the Spherical Panorama command to wrap the panorama so it’s continuous.
Be sure to photograph a full circle of images with sufficient overlap. Photographing with a pano head on a tripod helps produce better results.
For a video on creating a 360-degree panorama, see http://tv.adobe.com/#vi+f1577v1001.