The horizon is littered: Photosynth is worse than the panorama than the three-dimensional reviews

Today, I first met Photosynth as a spectator - so, probably, everyone gets acquainted with it: I installed Silverlight, restarted my browser, got into Bing cards, unscrewed the map to my city and started looking at who and what had time to pacify around it.

By chance, the first synth I got was called " Gelendzhik: View from the Mountains ." As soon as I opened it, without even touching anything, I instantly saw: the horizon was littered, the horizon was oblique. Although the author of the photographs kept the camera straight and even when shooting, Photosynth clearly distorted his pictures in this immediately visible part of the synth:


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At that moment, what an unattractive fact was revealed to me in all the shameful nakedness of it: despite the fact that Photosynth is advertised by Microsoft as a means of automatically stitching a whole heap of photos, which is enough to get there, and in fact achieve it. not always the case. In particular, it is not given to the photographer simply to turn his head and camera in different directions from one point, take a photo, and then throw his photos into Photosynth and seriously expect the appearance of the correct panorama at the exit.

And after all, exactly the same effect is manifested here, which was not described for the first year, for example, in the manual on PTGui : an automatic stapler, even reuniting such images that form a complete ring on a certain sphere, is not able to eliminate that part of their fluctuations the slope, the period of which is equal to 360 ° (that is, the length is exactly equal to the length of the development of the sphere). As a result, the horizon forms a sinusoidal curve, sometimes with a rather significant amplitude:



Only manual intervention of the photographer (indication and construction of the horizon at two points not opposing the sphere) can eliminate this unpleasant effect. But in Photosynth such an intervention is not possible.

Consequently, Photosynth should be used with the very purpose that is shown in their demonstration video : not to take a certain neighborhood view from one point, but rather to take pictures of the same object (or a whole series of objects) from different sides. Perhaps in this case, Photosynth assumes (and quite reasonably) the photographer moving in a horizontal plane, and in any case acquires a more complex view of the space being photographed than a simple sphere from a simple photo panorama.

The reverse is also true: ordinary photo-panoramas are better stitched by other means - after which they are also not used by Photosynth for hosting, but by Gigapan , or pan0 , or another similar site (say, spherical panoramas are accepted at 360Cities ).