A spyglass is a portable optical tool that can be extended according to the user’s need. It is a type of monocular spectacle: a tube with a lens on its end that increases the size of the images of those things located far away.
It is believed that the inventor of the spyglass was the German Hans Lippershey (1570-1619), who started from theoretical developments by other scientists to build the first telescope of practical use. Lippershey, however, did not obtain a patent for the invention. Building on the work of the German, Galileo Galilei finally managed to improve the telescope (which is an instrument equipped with mirrors or lenses to enlarge the image of an element located at a great distance).
The first spyglasses were used by naturalists to observe species and by sailors to try to spot land. Over time they began to be used in other observations, including in the field of astronomy.
In addition to the above, we cannot ignore the fact that there are basically two types of spyglasses:
-The ceiling spyglasses. They also respond to the name of linear and receive this name because they have linear prisms and objective lenses. They have the advantage that due to their size and weight, they are very practical to take on a trip as part of luggage. And it is that they are great when, for example, to make trips to discover the beauty of different natural places.
-The joint spotting scopes, which have the peculiarity that they use what are triangular lenses. They offer a non-linear view. Unlike the first, they are much heavier and need to be used using a tripod. Given these characteristics and many others, it should be noted that they become the best option to enjoy panoramic views from long distances. In the same way, this type of spyglass is the ideal one to carry out what are astronomical observations.
The main characteristics of spyglasses are their diameter and their degree of magnification. Larger diameter lenses allow more light to be captured and thus provide brighter images. The degree of magnification, on the other hand, refers to the possibilities of approach that the spyglass offers. Generally this grade is mentioned by a multiplier, such as 10x or 20x.
When purchasing a spyglass, three significant aspects must be taken into account:
-The use that is going to be given to it. And it is that based on the job that you want to grant you will have to choose to buy one type or another.
-The diameter of your lens, since the larger it is, it will capture more light and, therefore, will allow a much brighter image to be obtained.
-The degree of magnification that it offers because this way you can have some images or others with more details and proximity.
Currently, the use of spyglasses transcends the realm of science. In many tourist sites, spyglasses are installed so that visitors can enjoy panoramic views or try to spot animals that, with the naked eye, are difficult to detect.