A remarkable advance for the serious visual observer of emission nebulae. Unlike the wide transmission band characteristics of the Broadband Nebular Filters, Meade Narrowband Filters zero in on the three most important visible wavelengths emitted by deep-space emission nebulae: the two spectral lines of Oxygen III at 496 and 501nm and the Hydrogen Beta line at 486nm. Virtually all unwanted city light emissions are rejected by factors of 99.9+%. Because of its narrow bandpass characteristics, the Narrowband Nebular Filter achieves striking levels of contrast between the nebula itself and the surrounding dark-sky environment: objects such as the Orion Nebula (M42), the Lagoon Nebula (M8), and the Omega Nebula (M17) are observed as they would normally appear through telescopes of several inches larger aperture. Tenuous, faint outer extensions of these objects now become readily observable—often to the point where the visible mass of the nebula is more than doubled in diameter. Planetary nebulae such as the Ring Nebula (M57), the Dumbbell Nebula (M27), and the Saturn Nebula (NGC7009) similarly display dramatically-heightened levels of contrast and observable detail. Faint, insignificant patches of nebulosity that heretofore were near the limit of observability are now viewed with ease. The Meade Narrowband Nebular Filter should be viewed as a complement to, not as a substitute for, the Broadband Filter on the opposite page. The Broadband Filter enhances the performance of a much wider range of nebular objects; the Narrowband Filter improves contrast and visible detail on fewer objects, but in these more limited cases it does so to a most dramatic level. Because of the very narrow range of total light energy transmitted, the Narrowband Filter is not intended as a photographic filter. Visual effects of the Narrowband Filter are most pronounced when the filter is used with eyepieces of 25mm focal length and longer. #908N: Threads into the barrels of all Meade 1.25" eyepieces and most other 1.25" brands. Clear aperture: 26mm. #911N: Threads onto the rear cells of Meade LX-series mirror-lens telescopes and onto Meade ED Apochromatic Refractors, using the Universal Thread Adapter. Also threads to other brands of SCT's as well. Clear aperture: 36mm.
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