Dual Band filter for Vespera

The Dual Band Vespera filter is a dual narrow-band interference filter that significantly improves photo quality, whether you're observing from an urban or natural environment.

By precisely selecting the wavelengths of Hydrogen Alpha (H-alpha) and Oxygen III (O-III), found mainly in nebulae, the filter enhances the contrast between the stellar object and the background sky. This results in a superior image quality, with finer details and stars.

Let only the essential pass

The Dual Band filter has been designed to allow only two particular wavelengths to reach the Vespera sensor:
- O-III
- H-alpha

The filtered wavelengths make it particularly effective for photographing nebulae in emission (e.g. Orion nebula M42, Heart nebula IC 1805 ...), obscure nebulae surrounded by hydrogen (e.g. Horsehead nebula, Elephant Trunk nebula), planetary nebulae (e.g. Owl nebula M97, Moon nebula IC 1805 ...): Horsehead Nebula, Elephant Trunk Nebula), planetary nebulae (e.g. Owl Nebula M97, Dumbbell Nebula M27...), supernova remnants (e.g. Swan Lace, Crab Nebula M1).

For globular clusters (e.g. Hercules cluster M13, cluster M92...), the selectivity of the Dual Band filter makes it possible to obtain finer stars.

A custom-designed filter 

The optical quality of the Dual Band filter has been specifically studied by our engineers to offer full aperture use, without any impact on the instrument's optical diameter. The lens ring is equipped with an electronic micro-map that enables Vespera to detect the Dual Band filter and adapt its observation and image processing parameters.

Transmission curve

The filter has 12nm of bandwidth in each of the two wavelengths (O-III = 500.7nm, H-alpha = 656.3nm).