The Celestron Luminos ultra wide angle eyepieces use six to seven lenses to provide a huge 82° apparent field of view. They are designed to be particularly effective with high quality flat field telescopes, such as the Celestron EdgeHD flat field high definition catadioptrics, and refractors with field flatteners, such as the SkyWatcher Quantum refractors.
The view through a Luminos eyepiece is more like looking through a “picture window” on deep space, rather than looking through a constricted field eyepiece. The field stop that defines the edge of the image seems to disappear, immersing you in the view of the heavens.
Each eyepiece is fully multicoated and computer-optimized for excellent correction of chromatic and spherical aberration and astigmatism. The lens edges are blackened for high contrast. They are parfocal, to minimize the amount of refocusing needed when switching between eyepieces within the Luminos series. They may not be parfocal with other eyepieces in your collection, however.
Each eyepiece has a twist-up rubber eyecup to shield your eye from ambient light. The 7mm, 10mm, and 15mm focal lengths have 1.25” barrels that are threaded for standard 1.25” color and light pollution filters. The 19mm and 23mm versions fit 2” star diagonals and focusers only. The barrels of the 19mm and 23mm focal lengths are threaded for 2” filters. All have a no-slip wide rubber grip that assures secure handling, even when slippery with dew. A groove machined into the chrome barrel of each eyepiece acts as a safety stop to keep the eyepiece secure should the focuser thumbscrew loosen slightly while using the eyepiece. Supplied soft rubber caps seal both ends of each eyepiece to keep them dust free.
The eyepieces work well for low to medium high power observing with all telescope types and focal ratios, but particularly with flat field scopes. They have very good color correction, with virtually no field curvature, astigmatism, or ghosting. The optical performance is well corrected and sharp from edge to edge across the wide, wide field. The Celestron Luminos eyepieces are a good choice for observing large scale objects – open star clusters, nebulas, galaxy pairs like M65 and M66, etc.