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 acceleration. The g-force acceleration is the same as the specific force. The acceleration of an object free falling towards the earth depends on the reference frame (it disappears in the free-fall frame, also called the inertial frame), but any g-force "acceleration" will be present in all frames. This specific force is zero for freely-falling objects, since gravity acting alone does not produce g-forces or specific forces. Accelerometers on the surface of the Earth measure a constant 9.8 m/s^2 even when they are not accelerating (that is, when they do not undergo coordinate acceleration). This is because accelerometers measure the proper