Experimental phenomenology probes the meanings and qualities that compose immediate visual experience. In contradistinction, objective methods of classical psychophysics intentionally ignore meanings and qualities, or even awareness as such. Both have their proper uses. Methods of experimental
phenomenology that address "equivalence" in a more intricate sense than "visible–not visible" or "discriminable–not discriminable", require stimuli that go beyond the mere level of magnitude-like parameters and perhaps intrude into the realm of semantics. One investigates the cloud
of
Jan Koenderink, Andrea Van Doorn, Matteo Valsecchi, Johan Wagemans, Karl Gegenfurtner, "Eidolons & Capricious Local Sign" in Proc. IS&T Int’l. Symp. on Electronic Imaging: Human Vision and Electronic Imaging, 2017, pp 24 - 35, https://doi.org/10.2352/ISSN.2470-1173.2017.14.HVEI-112