FAQ

Photosynth Frequently Asked Questions

For technical support questions, information on how to make synths, or other inquiries related to the release version of Photosynth, see photosynth.com, the Photosynth team blog, or the Photosynth help section.

Photosynth.com 

Q:  What is Photosynth? 

A: Photosynth is an entirely new visual medium. Photosynth analyzes a set of photos of a place or an object for similarities each other, and uses that data to estimate where a photo was taken and build a model of the subject. It then re-creates the environment and uses that as a canvas on which to display the photos.  Photosynth is available for free at photosynth.com, where you can explore creations from users around the world and build synths of your own.

Q: What is different at Photosynth.com from the original technology preview?

A: The first question from nearly all of you who saw the tech preview:  When can I create my own?  You asked for it, you got it.  Photosynth.com enables you to experience synths contributed by other users from around the world, and to simply and easily create your own with nothing more than a few dozen photos of a place or object.

Behind the Scenes

Q: How does Photosynth work?

A Photosynth experience begins with nothing more than a bunch of digital photos. They might all have been taken by one person, or they might be a mixture of images from many different cameras, shooting conditions, dates, times of day, resolutions, and so on.

Each photo is processed by computer vision algorithms to extract hundreds of distinctive features, like the corner of a window frame or a door handle. Photos that share features are then linked together in a web. When the same feature is found in multiple images, its 3D position can be calculated. It's similar to depth perception - what your brain does to perceive the 3D positions of things in your field of view based on their images in both of your eyes. Photosynth's 3D model is just the cloud of points showing where those features are in space.

Your brain knows that your eyes are about two inches apart. But when Photosynth does its magic, it doesn't know where the cameras were, or which way they were pointing. Fortunately, when there are many cameras, and many features in common, the algorithms behind Photosynth can figure out not only where the features are in 3D, but where all of the cameras would have to have been, and which way they were aimed, consistent with the features they "saw".

The Photosynth viewer shows you the 3D point cloud, but more importantly, it also shows you the original pictures overlaid on the model. Imagine a slide projector placed at each original camera position, aimed how the camera was, and projecting the picture that camera took. A screen is placed in the 3D environment at an appropriate distance from the projector. As you move around in the Photosynth environment, projectors turn on and off, giving you a changing perspective on a world built entirely out of the original photos.

The Technology Preview

Q: Is the original Photosynth Technology Preview still available?

A: No, the original tech preview has been taken offline in favor of the more fully supported release at photosynth.com.  We have transferred most of the old synths to the new site, though a few we were unable to move for a number of reasons. But, rest assured, there are thousands of great synths on the new site to keep you engaged for a long long time. 

Photosynth Futures

Q:  Now that Photosynth has been released by Live Labs, where will it go from here?

A: Following this release, the Photosynth team will join MSN — an important step in continuing to improve Photosynth and share the experience with an even wider audience. In addition to letting users create and share synths at photosynth.com, over the next year Photosynth will begin to become a key part of the experience for MSN’s 550 million monthly visitors worldwide. Synths will be prominently featured on MSN.com. To create a more absorbing experience for its visitors, MSN will use synths of popular destinations and notable events in many of the places where static images are used on the site today.