What Are The Different Types Of Eyepiece Filters

What are the different types of eyepiece filters?

You have a brand new telescope, you have unboxed it. The installation process was a breeze. Dawn falls, and soon the sky is dark with shimmering stars.

Your first endeavor with your shiny new telescope. Observe the moon, track mysterious celestial bodies in all their wonder.

The moon is bright, but you miss an ultra HD view. What could impart more clarity to the telescope of your eyepiece?

The answer is simple and small. An eyepiece filter! There are several types of filters for different observations via your scope.

How eyepiece filters aid in your astronomical observations?

Eyepiece filters remain the unparalleled supplement for astronomers. They are particularly helpful in lunar observations.

They minimize eye strain by reducing glare, scattering of light, and enhancing contrast. Eyepiece filters employ selective filtration.

They improve the resolution of the image and reduce exposure to light rays. There are several types of eyepiece filters in the market today.

Scroll down to the next section for a comprehensive insight into eyepiece filters. We have elaborated three principal types of filters.

What are the different types of filters?

In this section, we touch upon colored, neutral, and polarizing filters. Each filter type has its function in different types of astronomy.

Blocking harmful light frequencies is the primary function of all-optical filters. Selective filtration of light frequencies enhances your observation.

You can view the details more clearly with both superficial and deep sky objects. Out of all these types of filters, three are of more importance.

Colored filters

Colored filters are also known as planetary filters. Frederick Wratten first invented them. The color numbering system is named after him- Wratten numbers.

In 1912, he sold his company to Kodak, Kodak then continued his legacy by manufacturing the Wratten filters for years to come.

Even today, astronomers use the warren numbering system for astronomy. The functionality of filters depends on the aperture, focal length, and magnification.

Dark-colored filters should be used in reverse for larger than 8 inches of apertures. There is plenty of room to experiment with different filter combinations.

Each planet has its characteristic color. A colored filter reduces the predominant hues.

This unravels the dramatic details of the celestial body you are viewing. When a colored filter is applied to an eyepiece, light scattering is highly reduced.

The earth’s atmosphere remains in a state of perpetual fluctuation. Due to this phenomenon, air current causes blurring of the finer details of the celestial bodies.

The contrasting margins blend into a condition called irradiation. Irradiation is responsible for the distortion between the lighter and darker regions of a planet.

Using a # 15 deep yellow colored filter, you block the UV light. Yellow #5 and #80A also reduce distortion.

The 382A pale blue colored filter can be stacked up together. This helps in bringing a color balance to your observations.

The #58 Green colored filter, blocks the amount of nebulae emission. #25 red is the best-colored filter for long exposure astronomy.

Eyepiece filter brings an apparent and immediate change to your observations. The polar caps on mars appear are bright tiny pearls.

The vague markings on Saturn become clear. Once you employ an eyepiece lens, you will unravel a whole new side to astronomy.

Neutral Density Filters

The neutral density filter fixes on a 1.25-inch eyepiece. The result is an Astro observation with reduced light exposure.

The amount of light entering the eyepiece after installing a filter is reduced to 87 percent. Lunar astronomy with a telescope can cause eye strain as the moon appears too bright.

The Neutral Density filter makes the endeavor more comfortable for your eyes. Only 13 percent of the total light rays pass through the eyepiece.

This filter is not color selective. Meaning, in contrast to the colored screen, these affect all spectrums of light.

It makes the image darker without causing any changes to the original color. These are especially useful for glare reduction and enhancing the contrast.

The filter is made out of glass, enclosed within a body of aluminum. You can stack different neutral density filters.

Polarizing filters

A polarizing filter consists of two-element that are polarized. These elements are independent of each other. They can be rotated freely without affecting the configuration of the other.

Similar to neutral density filters, polarizing filters reduce glare without changing the image’s color. You can manipulate the amount of light passing through with a polarizing filter.

When the filter positioned at the bottom is turned you, the transmission can be changed from 1 to 4 percent. This can significantly dim the brightness in lunar astronomy.

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