Just to put this into perspective, this is a 4.8% difference in sensor area. Or, linearly, it's 2.3% difference in crop factor. This is not very much, and generally _other_ measurement tolerances will be less precise. For example, if you measure the [actual focal length](http://photo.stackexchange.com/questions/13603/how-to-test-actual-focal-length) of, say, a bunch of different models of 50mm lenses, they probably have a _greater_ variation in field of view.