Shapere on observation

In his article "The Concept of Observation in Science and Philosophy" (1982), Dudley Shapere argues for an analysis of what it is for an object to be directly observed (observable). He does so by presenting two contrasting ways of observing the center of the sun. However, his examples, which are probabilistic in nature, are at odds with his analysis, which is absolute. I argue that of the three features of the examples which could serve as the basis for the analysis only one--the amount of alteration to the information being transmitted--can plausibly do so. Having reworked Shapere's analysis on the basis of this feature, I show that the analysis still fails to provide a sufficient condition for observation