Bresser EXPLORE SCIENTIFIC 2 O-III Nebula Filter 6.5nm

One of the most important obstacles for the exploration of the night sky is the brightening of the night sky by artificial lighting, such as street lights. The night sky is not really dark in the vicinity of towns or cities, which reduces the visibility of objects beyond the solar system enormously. Depending on the type of celestial object, it is possible to increase the contrast dramatically by blocking the interfering artificial light .

The EXPLORE SCIENTIFIC O-III filter uses a characteristic property of the so-called emission nebulae . Those objects glow in special colours, the so-called emission lines. Those emission lines are linked to chemical elements - in this case, oxygen. The EXPLORE SCIENTIFIC O-III nebula filter blocks all other colours (and thereby nearly all the artificial light) and only the two emission lines of the oxygen can pass the filter .
The result is astonishing: suddenly, nebulae are visible in locations that were completely empty without using filters. In suburban skies, for example, the veil nebula NGC 6992 is almost invisible with a 200 mm telescope. By using this filter, you can see the nebula and its structures without any difficulties. A must for every visual observer and for astrophotography .

The EXPLORE SCIENTIFIC nebula filters come with an individual test certificate - your guarantee for receiving a premium filter.

This filter's narrow passband of only 6.5 nm bandwidth highlights the faint emission nebulae or makes them visible even under difficult urban conditions.

FEATURES

• enables the observation of so-called emmission nebulae
• blocks almost the entire artificial light
• only the two emmission lines of the oxygen passes the filter
• band pass width: 6.5 nm
• narrow band version for difficult urban conditions
• allows more contrast for faint deep sky objects
• ideal for use near cities, in heavy brightened skies
• individual test certificate included to guarantee you receive a premium filter

SCOPE OF DELIVERY

• 1x 2'' O-III nebula filter