The Tele Vue-NP101is 4"/101mm Refractor Telescope from Tele Vue is a stellar leader in the field of high end imaging telescopes. Tele Vue's craftsmanship and optical excellence is legendary and this APO pushes the envelope of excellence. The Tele Vue-NP101is refractor offers a 540mm focal length with an f/5.4 in a precision crafted instrument designed for CCD astro-photography. The Nagler-Petzval design uses widely spaced doublets to produce a flat focal plane over a relatively narrow field of view. The "is" designation denotes an instrument capable of accepting Imaging Systems by offering a specific mechanical architecture for photography. The Tele Vue-NP101is is as optically, mechanically, and functionally near perfection as possible for imaging up to 50mm diagonal chips without detracting from the excellence of its visual capabilities.
The APO Nagler-Petzval refractor telescope has been provisioned with a Focusmate dual-speed focuser possessing a larger draw tube with a 3" front aperture and 2.4" rear aperture. The rack and pinion focuser holds up to 12 lbs of weight while providing the extremely fine focusing control of a 10:1 dual speed pinion assembly. The draw tube allows quick transition from imaging to viewing. It has an imaging insert ring with four lock screws which is threaded to accept optical items, cameras and CCD attachments. The focuser itself is a planetary ball type reduction focuser with extremely sensitive focus adjustment better than 1/10,000". A sliding metal dew shield, screw-on metal lens cover and a hard-shell carrying case are part of the package. Dark sky watching and imaging doesn't get any more satisfying than this.
The apochromatic refractor is the telescope design which produces the greatest breathtaking contrast and resolution, and Tele Vue doesn't skimp on the engineering. It won't deliver the light gathering capacity per dollar of Newtonian reflectors nor the portability of aperture of a Schmidt-Cassegrain. What it does deliver are views to be envied by both, with the darkest of background sky and the sharpest, widest fields imaginable. Combined with Tele Vue eyepieces, the experience cannot be bested by anything one would consider portable.