How does canon 550d setting machine shoot the effect of blurred background?

The background is blurred, and the large aperture controls the depth of field. If the head of the machine is blurred, just adjust the head to the telephoto end of 55mm, use the aperture priority mode AV, and adjust it to the maximum aperture, which may be 5.6, so that you can get the desired effect, but it is better to have some contrast between the colors of the target and the background, and the effect will be better.

Dear, to truly enjoy "the sharpness of a focused blade and the creamy melting of Jiao Wai", you must pay for it. 135mm f2 L USM is the best choice for a portrait, and 24-70mm2.8l USM is the king of standardization. I can't stand being hurt. This life is worth having.