check any plant with any possibility of lack of turgor _ i.e., droopy leaves. Even when drought is not apparent, it is best to check leaves as early in the morning as possible. ADVANCED USE (blurry line) A less-than-sharp demarcation line (blurry/fuzzy/diffused) on the screen is an indication of varied atom distribution _ i.e., an excellent mixture of minerals. For instance, many veteran refractometer users grow forages for animals and also have access to standard lab tests (so as to make possible direct comparisons of brix vis--vis other lab tests). They are adamant in insisting a sharp demarcation is an indication of increased simple sugar and therefore lesser high-quality protein ( and other life-enhancing substances ) at any given brix level. Conversely, they suggest a blurry/fuzzy line predicts more, and better quality, proteins (*). Interestingly, the fuzzy line concept appears to be supported by the ability of astronomers to use refracted light to determine the elemental makeup of distant stars. Starlight, properly refracted, is spread out so that the lines left by various elements can be identified. It is suggested that you think of your readings as, say, 12S (sharp) or perhaps 14D (diffuse). In almost all cases, blurry tastes better. You will quickly, and easily, learn to judge the mid-point of any blurring. Your correct reading lies there. Blue intensity matters on those models that have a blue background field. When different items reveal the same brix but one has a less intense blue, it will taste sweeter and