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This paper is about changes in the author's visual perception over most of his lifetime, but in particular in the period
before and after cataract operations. The author was myopic (-3D) until the operations, and emmetropic afterwards –
with mild astigmatic aberrations that can be compensated with cylindrical spectacles, but in his case rarely are, because
of the convenience of not needing to wear distance glasses in daily life anymore. The perceptual changes concern color
vision, stereopsis and visual acuity. The post-cataract changes were partly expected, for example less yellow and more
blue images, but partly wholly unexpected, and accompanied by feelings of excitement and pleasure; even delight. These
unexpected changes were a sudden, strongly increased depth vision and the sensation of seeing suddenly sharper than
ever before, mainly at intermediate viewing distances. The visual acuity changes occur after, exceptionally, his distance
glasses are put on. All these sensations lasted or last only for a short time. Those concerning stereopsis were dubbed
'super depth', and were confined to the first two months after the second cataract operation. Those concerning acuity
were termed 'super-sharpness impression'; SSI. These can be elicited more or less at will, by putting on the spectacles
described; but will then disappear again, although the spectacles are kept on. Ten other ex-cataract patients have been
interviewed on their post-operation experiences. The 'super-depth' and SSI experiences may be linked to assumed
neurophysiological mechanisms such as the concept of Bayesian reweighting of perceptual criteria.
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