Method Of Using The Barlow Lens In The Telescope Stock Photography

In its astronomical use, a Barlow lens may be placed immediately before an eyepiece to effectively decrease the eyepiece`s focal length by the amount of the Barlow`s divergence. Since the magnification provided by a telescope and eyepiece is equal to the telescope`s focal length divided by the eyepiece`s focal length, this has the effect of increasing the magnification of the image.Astronomical Barlow lenses are rated for the amount of magnification they induce. Most commonly, Barlow lenses are 2x or 3x, but adjustable Barlows are also available. The power of an adjustable Barlow lens is changed by adding an extension tube between the Barlow and the eyepiece to increase the magnification.