How to take photos of the front and back?

The effect of taking pictures with the front solid and the back virtual is that the camera only captures the light refraction of the front object, but not the refraction of the back background, so it has already cut into the shutter. So you need to use a very fast shutter, and a faster shutter needs a larger aperture to have a normal exposure photo. Only when the maximum short focal length is used can the maximum aperture of the camera be achieved. The largest short-focus camera takes a panoramic view, and it is necessary to try different configurations for close-range objects that cannot achieve the effect of real front and virtual back.