Which is cheaper, a starlight mirror or a polarizer?

The excellent function of polarizer is that it can selectively let the light that vibrates in a certain direction pass through, and it is often used to eliminate or weaken the strong reflection of non-metallic surface in color and black-and-white photography, thus eliminating or reducing the light spot.

The starlight mirror will produce different effects of star flash according to the number of thin lines engraved on it and the pattern formed by thin lines. It is usually used to shoot the reflection of light or objects at night, so as to achieve the radiant effect and make the photos have fantastic artistic effects.