OWL Astronomy

OWL Astronomy Products
Eyepieces, Telescopes, Binoculars, Microscopes
Nebula/Light Pollution Filters





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Premium Quality 1.25 Inch IR Blocking Filter
Brand New in Box

Specially designed to remove all of the IR from the image.
A large portion of the UV also is blocked.

This filter is almost essential for color CCD photos.

Fit all Standard 1.25" (31.75 mm) Diameter Eyepieces


The multi-layer coating on the IR Blocker filter makes it appear various shades
when you look at the light reflected from it. This filter appears colorless
when you look through it because it passes all visible light. (This filter
looks blue-green here, but shows different colors from other angles.)

Filter is protected by a sturdy plastic case.

This filter is just about essential for color photography of deep-sky objects using CCD/Digital cameras. This IR blocker filter passes all light except for the IR (infrared) and most of the UV (ultraviolet). While these wave lengths are invisible to the human eye, they are very photographically active. All CCD/Digital cameras are very sensitive to IR. If you do not have an IR filter in the line and try to do tri-color photographs, the IR is passed by many of the filters of various colors. A blue filter, for example, that passes IR will end up with a much less saturated photo because the blue will be contaminated with the IR. In addition any telescope with a lens will not focus the IR at the same point as the visible light. This results in a out of focus blur on those objects that have an IR component.

Note that all critical nebula lines and all other light except for IR and UV are transmitted at close to 100%. The unwanted IR is blocked completely. This filter passes a continuous spectra of visible light.

These filters will fit all major brands of 1.25" (31.75 mm) eyepieces. These brands include Meade, Orion, Tele Vue, Celestron, and our own Knight OWL series. These filters are a great value at this great price.

1.25 Inch (31.8 mm) IR Blocking Filter
Short Term Sale Price Only: $22.95.
Note: IN STOCK



High Quality 1.25 Inch and 2 Inch Nebula Filters (UHC)
Ultra High Contrast (Narrow-band) Filter

Filter Eliminates Many Light Pollution Problems
While Giving the Highest Nebula Enhancement
Brand New in Box

Specially designed to increase the contrast
for all deep-sky visual or photographic observations

Fit all Standard 1.25" Diameter or 2" Diameter Eyepieces


The coating on the Nebula filter makes it appear various shades when you look at
the light reflected from it. It appears cyan (blue-green) when you look through it.

With a dark surface behind it, this filter looks almost
like a mirror because of the amount of unwanted light reflected.

This Ultra High Contrast (UHC) filter is great for giving the maximum enhancement of nebula. It also acts as a light pollution filter to remove most artificial light. It blocks all high and low pressure mercury and sodium vapor lamp light, neon lights and sky-glow. It is excellent for both visual and photographic applications. For visual observations, this filter is great under dark or somewhat light-polluted skies. It greatly enhances nebulae and comets relative to the background light. While it is especially good for nebula, by darkening the background of space, this nebula filter provides a better view of all deep-sky objects.

Photographically, a good nebula enables deep space photos of nebulae, star clusters and galaxies to be taken even where you have light polluted skies. It is valuable even at good dark-sky sites because it blocks the natural sky-glow spectral line at 558 nm. Because of this, it provides higher contrast deep sky photographs.

Note that the critical astronomical lines for hydrogen beta, oxygen three, and cyanogen are transmitted at close to 100%. The unwanted light from mercury vapor, high and low pressure sodium, and sky-glow are completely removed.

Typical transmissions for these filters are:
486 nm Hydrogen-Beta 95%
496 nm Oxygen III 94%
501 nm Oxygen III 95%
656 nm Hydrogen-Alpha NA*
* NA - Not Applicable: UHC filters are not normally used for Hydrogen-Alpha because only a portion is transmitted. They do transmit essentially all of the infra-red.

These filters will fit all major brands of 1.25" (31.8 mm) or 2" (50.8 mm) eyepieces. These brands include Meade, Orion, Tele Vue, Celestron, and our own Knight OWL series. These filters are a great value at this great price.

Very good nebula and light pollution filters available at great prices.
Sale Prices for a short time only!

1.25 Inch (31.8 mm) UHC Filter
Short Term Sale Price Only: $36.95.
Note: IN STOCK

2 Inch (50.8 mm) UHC Filter
Short Term Sale Price Only: $68.95.
Note: IN STOCK

High Quality 1.25 Inch Nebula Filters
Light Pollution/Broad-Band Nebula Filter

Gives very great contrast of the nebula against a black sky
(Also excellent for all other deep-sky objects
because it greatly reduces light pollution)
Mercury and Sodium Vapor and Sky-Glow are removed

Fit all Standard 1.25" Diameter Eyepieces

This broad-band filter nebula and light pollution transmits over an area of the spectrum that is centered on the Hydrogen-beta and Oxygen-III lines. It also transmits light in the red part of the spectrum. While it is very good for emission nebula, this filter also gives good light pollution reduction making it good for galaxies, star clusters, and other nebula. The light pollution reduction is due to removal of all mercury and sodium vapor spectral lines. All sky-glow is removed.

These filters will fit all major brands of 1.25" (31.8 mm) eyepieces. These brands include Meade, Orion, Tele Vue, Celestron, and our own Knight OWL series. These filters are a great value at this great price.

Very good nebula and light pollution filters available at great prices.
Sale Prices for a short time only!

1.25 Inch (31.8 mm) Light Pollution/Nebula Filter
Short Term Sale Price Only: $34.95.
Note: IN STOCK



Last June 24, 2012

Site Map Use the above menu with most browsers. Use the site map on the left with old browsers or cell phones.