1.25" Skylight Filter

The Astronomica skylight filter is an excellent multi purpose filter.  It is a contrast boosting filter, which every observer will find extremely useful.  This filter is suitable both for beginners and advanced observers. It can be used on all sizes and types of telescope successfully.  It is highly recommended on small telescopes, where conventional filters would block out too much light.

In terms of application, this filter is extremely versatile. Firstly it can be used on solar system objects: On Jupiter, it provides a strong contrast gain on reddish details, like the Great Red Spot and compared with a normal colour filter the resulting image will have more natural colour hues. Mars is a planet with notoriously weak contrast between its dusky features. By using the Astronomica skylight filter previously invisible detail will become visible.  It is especially successful at enhancing the visibility of the polar caps. On the moon, the filter reduces glare and improves contrast, in particular with detail positioned in the usually apparently featureless regions away from the terminator.

On gaseous nebulae, the Astronomica skylight filter is similar in function to a broadband nebular filter.  It boosts an objects contrast, especially in the red H-Alpha emission line and the sky background is reduced in brightness.  The filter is also effective in other wavelengths. The Astronomica skylight filter is less aggressive compared to narrow-band filters, producing a more 'natural' appearance in objects

Observations at twilight are made easier, as contrast is improved, by reducing the blue glare of the sky, resulting in a darker background. The contrast of objects is also boosted during daytime applications, without causing excessive unnatural coloration.

The filter cell is machined and black-anodized with threads on both sides (male on one side and female on the other), so you can stack this filter with other 1.25" filters. Its clear aperture is a full 26mm. The filter glass is scratch resistant and the glass used is of very high optical quality.

The Astronomica skylight filter filter comes in a protective, foam-lined, plastic storage case.