![]() ![]() ![]() It's a bit like trying to set fire to a match-head. and hopefuly we have a picture rather than a black frame. but we don't want t ALL black, so we have to let the solution get to work, but stop it before it's finished. there's enough oxidsing agent it, to turn every bit of silver halide into silver oxide. we are trying, because we are actually relying on it to create a 'partial reaction'. what we want to do is, turn the sliver halide that has been partially oxidised by light into silver oxide, and NOT oxidize that which hasn't. we don't want to turn ALL the silver halide we have to silver oxide. In photography, however we are trying to 'cheat' the chemistry and deliberately NOT get a 'complete' reaction. It's been two many years since I had to balance equations, and I haven't had enough coffee yet to do the maths, but you could, 'balance' the equation to put the correct proportions in so you have as much C,H&O on one side as other. only what you have to start, you have to have at the end, so while that equation describes the chemicals you start with, and what they get turned in to, it's not quite right as far as the quantities, because I started with CH4, which is one carbon and four hydrogen, at the end, I have one carbon in the CO2, but have lost a few hydrogen with only one in the H2O. you are actually deliberately trying to cause what in chemistry would be known as an 'incomplete reaction'įor example, chemical equation for burning methane, in oxygen, is CH4+O2=> CO2+H2O. in the tank, you are doing the same, 'boosting' that reaction, and getting tickled areas to turn black, and untickled ones to stay white. Where light falls, it starts to oxidise, where it doesn't it doesn't. In the camera, making an actual exposure, you are trying to 'cheat' the chemistry where light falls it catalyses the oxidisation reaction of the silver halide emulsion. Really, the twizzle is a common part of the sport, which is why an expert commentator can say the word over and over again without realizing how ridiculous it sounds to the uninitiated.In chemistry, rates of reaction are proportional, among other things, to temperature hotter the environment, usually the faster the reaction hence in colour processing the 'adjustments' for different bath temps then it is proportional to solution concentrations which s why in B&W you often have different dev times for mixing solutions at different strengths, say 3:1, 5:1 & 9:1. When looking at twizzles, judges assess the difficulty of the position, the closeness of the partners to each other, and various other factors. The most common type occurs in an upright position with the free foot kept close to the skate leg. They can be clockwise or counterclockwise, on different edges of the skate, and forward or backward. Naturally, twizzles also come in different shapes and sizes. That specific movement is crucial, because it differentiates the twizzle from a stationary spin or series of turns. For a twizzle, a skater executes a one-foot turn and also moves across the ice, keeping the turning movement continuous. More specifically, it's a turn common to ice dancing and seen less commonly in the figure skating American fans might know best. There's a simple answer: a twizzle is a turn. But what exactly is a "twizzle," other than a funny term that makes for very easy Twitter jokes? Did skating authorities make it up to seem hip? And does it have anything to do with candy? During NBC's Saturday night coverage of the figure skating team competition, commentators routinely referred to the twizzle in the routines of various ice dancers such as Team USA's Meryl Davis and Charlie White and reigning gold medalists Tessa Virtue and Scott Moir of Canada. ![]()
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