Bresser EXPLORE SCIENTIFIC 1.25 H-Alpha Nebula Filter 7nm

Apart from air turbulence, the brightening of the night sky is the greatest barrier to observing faint objects beyond the solar system. Due to streetlamps and other artificial lighting the sky in urban areas is no longer properly black. As a result, the contrast and thus the perception of deep-sky objects also suffer. However, depending on the type of celestial object, it is possible to filter out some of the interfering light making it easier to photograph the objects.

The EXPLORE SCIENTIFIC H-Alpha filter uses the characteristic of the so-called emission nebulae. These objects glow in certain colors, the so-called emission lines. The emission lines are associated with certain chemical elements - in this case the red glowing hydrogen. This filter blocks all other colors (and therefore almost all artificial light) and lets only the emission lines of hydrogen through. Especially the disturbing light of mercury and sodium vapor lamps is effectively blocked. The effect is amazing: Suddenly, nebulae become visible on the photos in places which appear completely empty without the filter.

The EXPLORE SCIENTIFIC H-Alpha Nebula Filter has been developed exclusively for astrophotography. Especially in heavy light-polluted skies  many emission nebulae are only visible and shown in full expanse on astrophotos when using this filter. The H-Alpha nebula filters make astrophotography near the city possible and the use leads to amazingly good image results despite the existing light pollution. A must for every urban astrophotographer.


FEATURES

• H-Alpha filters are used exclusively for astrophotography
• Allows photography of emission nebulae that glow in the light of red hydrogen
• Many of these emission nebulae are only visible in their full expansion on photos taken with this filter
• Blocks almost all artificial light, especially from mercury and sodium vapor lamps
• Only allows the emission line of red hydrogen to pass through
• Narrow band version for difficult urban conditions
• Transmission bandwidth: 7 nm
• Allows more contrast and detail for all urban astrophotographers
• Ideal for use near cities, in heavy brightened skies
• Individual test certificate included to guarantee you receive a premium filter

SCOPE OF DELIVERY

• 1x 1.25'' H-Alpha Nebula Filter