In theory having different wavelengths converge at different locations should affect the luminosity and blur high-contrast edges or create ghost-like images of them, in practice however it seems that the color fringing is always to the darker side of the high-contrast edge and BW conversion shows no artifacts near the CA affected areas.

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A camera lens, uncorrected, displays each color coming to a focus at different distances from the lens. This was not a big problem for early films, they were sensitive only to violet and blue. These films have a chemical focus that differs from the visual focus. Easy to solve, the sheet film holders positioned the film to compensate.

Early corrective lens forced red and green to focus at the same distance. Because each color comes to a focus at different distances from the lens, each image is slightly different as to size (magnification). Thus a panchromatic film images only one color tack sharp, the other colors are slightly out of focus.

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