[Note: I updated this blog entry in August 2013 to include information about a great panorama tool called PTgui and to provide more info about taking panorama photos.]
A panorama overlay can give you the impression that you’re inside a building or cockpit, allowing you to spin around and zoom in and out. Creating the source files for panoramas is not easy, but if you use the right tools and equipment, the process can be painless—and even fun.
A panorama overlay requires six images that represent the inside of a cube. Here are the six images used for the courtyard panorama that appears in the DPS Tips app (Overlay Basics > Panoramas).
You can use Photoshop to stitch together the source image to be used as the basis for the six cubic images. However, converting a 3D panorama image into the six images requires a third-party tool such as PTgui or Pano2VR. PTgui and Pano2VR cost about the same amount, but PTgui is more versatile. With PTgui, you can stitch together the images to create the source file and then generate the six images from that source file.
Here’s how to create the images required to build a panorama overlay in DPS.
1. If necessary, do a photo shoot.
The method you use for taking photographs depends on a number of factors, including the type of camera equipment you have, the amount of detail you want the panorama to include, and the type of panorama effect you want.
With a fisheye lens, you can create a full 360-degree panorama using as few as three photographs. With a wide-angle lens, you can create a 360-degre panorama using as few as eight photographs, but you probably want to use more. With a camera that doesn’t have a special lens, you’ll need to take a lot of photographs, and you’ll probably need to take sets from multiple angles: high, medium and low plus top and bottom. When shooting your images, the key is to provide enough overlap to allow a software program to stitch together the images.
For some panoramas, such as a cockpit or a cavern, you’ll want a full 360-degree experience in all directions, left and right, up and down. For other panoramas, such as a room of paintings in a museum, you might want to limit both the tilt and rotation.
For detailed information about how to take panorama photos with different types of cameras, see http://www.vrwave.com.
2. Create or obtain the base panorama image.
One method is to drop the images in Photoshop and use a technique such as Photomerge. It’s a lot of work. You need to have a good set of pictures and advanced Photoshop knowledge to come up with a clean “equirectangular” source image such as this:
If you use a third-party tool such as PTgui that is specifically designed to create panoramas, you can generate the base panorama image more easily. And if things go wrong, you can clean up the image set, like this:
3. Use a third-party tool to output the six cubic images.
Once you get your source image, use PTgui or another tool to export the six cubic images. Use JPG or PNG files.
You might need to touch up the images in Photoshop or Lightroom.
4. Create a Panorama overlay.
Copy the six source images into their own folder, and create a panorama overlay that targets the folder. Then test the panorama to make sure it works properly.