Tan took more photos than is strictly necessary for an object synth and his photography is also relatively highly structured - reminiscent of what was necessary to achieve acceptable results with earlier tech like QuickTime VR's 'Objects'. Example: http://bit.ly/qtvrobjectgallery
What anyone will notice is that, because photosynths are general purpose (with scene structure being unpredictable), all imagery is loaded 'on demand'. Although you have automated image matching, no real resolution limits on images, ability to change distances from one's subject, etc. this means that for the simple purpose of having a spin movie/object movie experience, photosynths are not an ideal comparison to QTVR Objects because the illusion of turning a single object is broken when all images in an object movie/spin movie are not preloaded into RAM.