How to shoot the effect that the blurred light turns into a circle when shooting at night?

When shooting at night, it is necessary to shoot the effect that the blurred light becomes a circular spot. When shooting, you can use Av files, try to use a large aperture, and try to blur the background. The blurred point light source becomes a circular spot, and one is a circular spot, which is shot with a folding lens. Because the light is weak at night and the shutter speed is slow, it is recommended to use tripod and cable release (or delayed self-timer of camera) to ensure clear photos.

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