Joe,
it doesn't matter what the abstract observer is, it could be a mathematical point or a term standing for the processing of an equation into an output. The abstract observer represents the acquisition of information. That's what an observer real or abstract does. Beyond that the information must be processed as that is how something is known from the information. Sight is the product of processing received information. The product is a representation or construct it is not the external material reality, the source of the information. Convection currents in air can be used to demonstrate that as they can affect the distribution of the information prior to receipt. That is not speculation.