Canon 60D wide-angle shooting uses 18-200. Why does it always have purple edges? Still very serious. How can I set it to avoid purple edges when shooting?

First, if possible, try not to use a large aperture, so the purple edge is particularly heavy.

Second, the purple edge of backlight or side light is heavier than that of smooth light.

Third, your 60D has built-in RAW development, which can easily remove purple edges. In addition, Canon users have DPP image processing software, and he has the same function.

Fourth, your 18-200 is a large zoom lens, which inevitably has many purple edges. If you want a high-quality lens, you should either use a fixed-focus lens or an expensive red-circle lens.