Explore Scientific uses ED (Extra-low Dispersion) FCD1 (Dense Fluor Crown) glass developed by Hoya Optical of Japan to enable the production of lenses that offer superior sharpness and color correction by minimizing the color dispersion (chromatic aberration, or the "false" color fringing seen around bright objects that happens when light rays pass through standard crown-and-flint doublet objectives). This glass type offers a more durable and long lasting solution to produce an optic to minimize chromatic aberration over delicate fluorite crystal objectives that are prone to fracturing and absorbing moisture.
Exploring the fine features around the Moon's Hadley Rille will put to test observing skills of any astronomer as well as precision of telescope optics. Better optical quality dictates more precise focusing.
This is especially true when observing at high magnification or when making CCD images. With a standard focuser, you will find that a tiny nudge will throw out focus and turn your night into one of frustration.
So Explore Scientific includes as standard equipment, on all Explore Scientific ED Apos, a ten-to-one, two-speed Crayford-style precision focuser with tension adjustment and lock to obtain and hold perfect focus. We think you'll agree that such precision is worth it.
You can mount the ED 80 to many popular equatorial and Altaz mounts, including Explore Scientific's new TwiLight I and TwiLight II Altazimuth Mounts. Photographers, who are looking for super high resolution optics, can mount the optical tube assembly to their existing medium-duty camera tripod. A release knob allows the tube assembly to rotate so that the camera can be positioned at any angle.
All Explore Scientific telescopes and telescope accessories are covered under our standard U.S.A. One Year Limited Warranty against defects with proof of purchase, but you can extend this limited warranty to five years by simply filling out the product registration and mailing it in within 60 days.