<img src="https://www.travelsouthdakota.com/sites/default/files/styles/hero_l/public/2019-10/mtrushmorebychadcoppess_3.jpg?h=7549df8d&itok=oVEm9ks_" />

<img src="https://www.travelsouthdakota.com/sites/default/files/styles/hero_l/public/2019-10/mtrushmorebychadcoppess_3.jpg?h=7549df8d&itok=oVEm9ks_" class="darken" />

<div class="bg">With BG Image</div>

img { width: 40%; margin: auto;}

img.darken {
  filter: brightness(50%);
}

.bg {
  margin: 2rem auto;
  outline: 1px solid orange;
  height: 25vh;
  width: 40vw;
  background-image: linear-gradient(rgba(0, 0, 0, 0.527),rgba(0, 0, 0, 0.5)) , url(https://www.travelsouthdakota.com/sites/default/files/styles/hero_l/public/2019-10/mtrushmorebychadcoppess_3.jpg?h=7549df8d&itok=oVEm9ks_);
  background-size: contain;
  color: #fff;
}
/*

Question
https://www.sitepoint.com/community/t/is-there-a-css-and-or-js-hack-to-effect-the-darkness-of-a-background-image-directly/432222 */
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