With this 2-Inch O-III Nebula Filter you can now crank up the contrast between nebulae and the sky to reveal more of their wondrous details! Orion's Oxygen-III telescope filter provides extremely selective filtration to bring out elusive detail in diffuse and planetary nebulas. It does so by transmitting close to 90-percent of the light corresponding to the two oxygen-III spectral lines at 496nm and 501nm while completely blocking virtually all other wavelengths.
The results are remarkable. You'll see more detail than you ever could before in nebular gems such as the Swan, Ring, Dumbbell, Helix, and Eagle, to name a few. The O-III provides an even greater contrast boost on some objects than the UltraBlock narrowband telescope filter. And for nebulas, every little bit helps! Try the Oxygen-III telescope filter with a low-power 2-inch telescope eyepiece and take in the whole Veil Nebula. Wow!