Optolong Clear Sky Filter 77mm

Optolong Filters Clear Sky Filter 77mm is specially designed for photographers who want to enhance starry skies, auroras and night shots with wide-angle lenses. The filter has a 77mm filter thread and can be screwed directly in front of photo lenses, making it a practical solution for astrophotography in combination with DSLRs and system cameras.

The filter blocks disturbing yellow light from, for example, street lamps, something that is not easy to correct in post-processing. This darkens the sky background and significantly improves the contrast of stars and deep-sky objects. The applied neodymium oxide in the optical glass intensifies red and brown tones, which provides additional depth and vividness not only in astrophotography but also in nature photography, twilight images and autumn colors.

Unlike commonly used interference filters (such as CLS or UHC), this Clear Sky filter also works for wide-angle shots. In fact, interference filters rely on perpendicular light, making them often unsuitable for wide fields. This filter enables wide-angle photos of the Milky Way or aurora without complicated intermediate rings or mounting solutions.

Application
The Optolong Clear Sky filter is ideal for night photographers who want to capture the starry sky or aurora with wide-angle lenses, as well as for creative nature photography at dusk or sunset. It is not intended for visual observation through a telescope, but purely for photographic applications.

Specifications

• Type: Broadband filter
• Diameter: 77 mm (filter thread for photo lenses)
• Material: Glass with neodymium oxide
• Mount: Aluminum
• Coating: Multiple plane-parallel coating
• Application:
  • ✓ Photography with wide-angle lenses
  • ✓ Anti-light pollution
  • ✓ Galaxies and star clusters
  • ✓ AllSky and meteors
  • ✓ Aurora and Milky Way shots
  • ✗ Visual use by telescope not suitable