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 force Specific force Specific force is defined as the non-gravitational force per unit mass. Specific force (also called g-force and mass-specific force) is measured in meters/second² (m·s) which is the units for acceleration. Thus, specific force is not actually a force, but a type of acceleration. However, the (mass-)specific force is not a coordinate-acceleration, but rather a proper acceleration, which is the acceleration relative to free-fall. Forces, specific forces, and proper accelerations are the same in all reference frames, but coordinate accelerations are frame-dependent. For free bodies, the specific force is the cause of, and a measure of, the body's proper