The Unkindness of Ravens were inspired by figures from Norse and Celtic mythology such as the Valkyries and The Morrígan. Filming took place during 2014 in Fife, Edinburgh, and Perthshire, and moved into post-production in 2015. To help with costs, Brewster opened a crowdfunding campaign through Kickstarter, with the goal to raise £40,000. The campaign was successful and marked the first Scottish crowdfunding campaign to raise such a large amount of money and the highest funded British horror film on Kickstarter. Horror film critic Kim Newman reviewed "The Unkindness of Ravens", writing that it was "a demanding, complicated film which might well require repeat
Specific energy Specific energy Specific energy is energy per unit mass. (It is also sometimes called "energy density," though "energy density" more precisely means energy per unit volume.) It is used to quantify, for example, stored heat and other thermodynamic properties of substances such as specific internal energy, specific enthalpy, specific Gibbs free energy, and specific Helmholtz free energy. It may also be used for the kinetic energy or potential energy of a body. Specific energy is an intensive property, whereas energy and mass are extensive properties. The SI unit for specific energy is the joule per kilogram (J/kg). Other units still