Bokeh Quality: Why “Cat’s Eye Bokeh” and “Onion Rings” Appear
Bokeh isn't just about how much a lens blurs the background. Its appearance is determined by an entire range of optical properties—from the shape of the aperture blades to internal lens design and optical aberrations. Let’s take a look at how bokeh is rendered, what causes “cat’s eyes” and “onion rings,” and how your camera body itself can influence the appearance of bokeh.