Whether bird watching, or star gazing, a decent pair of binoculars always comes in handy. Some people are unaware that there are two different types of binoculars; prismatic binoculars and field glasses. Although the two terms are frequently used interchangeably, there are some fundamental differences:
Prismatic binoculars are the most popular type of binoculars as they offer greater magnification in a compact package. However, the inclusion of internal prisms makes them less robust than field glasses. As the title suggests, they use a set of prisms within each tube which reflect light as it passes though, allowing a greater path length to show. This creates higher magnification, thus allowing the binoculars to be shorter and the separation of the objective lenses to be wider.
Field glasses have no internal prisms that can be knocked out of alignment so their main advantage is that they are durable, making them a good choice for combative outdoor pursuits. They use both the objective lens (the large lens which captures light initially) and a second lens inside each tube, which inverts and reverses the image to make it appear the right way up. However, field glasses can only magnify an image by five times at best. The increase in size and weight needed to increase their top end magnification would make them far too impractical to use.
For more information and to view a comprehensive range of pocket binoculars, visit Sherwoods Photographic, a family owned company who specialise in telescopes and binoculars.