The Orion 80mm ED Apo Refractor Telescope Optical Tube is wonderfully suited for visual applications on both solar system and deep-sky objects as well as for prime-focus astrophotography and CCD imaging with it's focal length of 600mm (f/7.5). It sports a multi-coated 80mm objective lens doublet, one element of which is crafted from Extra-Low Dispersion, or "ED" optical glass.
This high-grade glass greatly reduces the chromatic aberration inherent in standard achromats. Images appear more sharply focused and color fringing around bright objects is lessened dramatically. The objective lens is held in a machined, black anodized aluminum cell and shaded by an aluminum dew cap. Internal tube baffles ensure high contrast and prevent ghosting.
The ED80 features a superb, backlash-free 2" Crayford-style focuser, which accepts both 2" and 1.25" diagonals. The focus wheels are classy, brushed-aluminum hubs with ridged rubber grip rings. Set the focuser tension or lock it for imaging with the focus lock knob. The molded-in dovetail base accepts the optional Orion finder scope of your choice. Tube has a built-in 1/4"-20 plate. At a length of just 24", the ED80 is extremely portable.