Cataract Colors
Cataracts cause Temporary Tritanopia
These pilot study made a variety of visual measurements before, during, and after bilateral cataract surgery. This article describes the changes in color discrimination and color appearance resulting from cataract implants. It used the F-M 100 Hue Test, color matching of real scenes, and color- balance titration measurements. The pre-surgery data indicated that the previously normal color observers had severe tritanopic anomalies. Lens replacement restored normal color vision.
Observers reported that a Wratten CC 40Y filter over the PostOp eye made colors in both eyes appear the same. The cataract introduced a substantial spectral modification affecting cone quanta catch. Comparing the substantial changes in cone quanta catches with the modest changes in appearance suggests the influence of color constancy mechanisms. Nevertheless, color appearances in PreOp vs. PostOp eyes were constant over 100 days. There was no evidence of chromatic adaptation, namely adjustments of relative cone response weightings. Brightness and color appearance changes were immediate and constant.
Compare Appearances
1 day after surgery 100 days after surgey
J.J. McCann and M.A. McCann,
“Temporary Tritanopia: Effects of cataract surgery on color”
Proc. IS&T Color Imaging Conference, Paris, 22, 278, (2019).
J.J. McCann and M.A McCann,
“Colors before and after cataract surgery:
A study of color constancy and discrimination”,
Proc. Electronic Imaging: Color, IS&T, San Francisco, COLOR-236, (2020).
<https://doi.org/10.2352/ISSN.2470-1173.2020.15.COLOR-236>
Illustrations of glare in: cameras, normal vision, and cataracts
Camera optics
adds light
raising the
cameras's
responses
18 year old observer
with normal vision
identifies
30 different
scene segments.
80 year old observer
with cataracts
identifies
10 segments.
20 segments appear black.
J.J. McCann,
“Increases in scattered light causes increased darkness”,
Proc. Electronic Imaging: Color, IS&T, San Francisco, COLOR-279, (2020).
<https://doi.org/10.2352/ISSN.2470-1173.2020.15.COLOR-279>