QED effect on a black hole shadow

Taking QED effect into account, we investigate the shadows of a static black hole with magnetic monopoles and neutral holes in fields through numerical backward ray-tracing method. For monopole, obtain relation between shadow radius coupling constant. uniform fields, find that curves deviate very little from ellipses for an equatorial observer, read linear eccentricity ${\ensuremath{\theta}}_{o}\ensuremath{\ne}\ensuremath{\pi}/2$, can be well approximated by most cases, except when field is strong observer sits around angle ${\ensuremath{\theta}}_{o}=\ensuremath{\pi}/4$ or $3\ensuremath{\pi}/4$. Moreover, extend our investigation to surrounded current loop.