Optolong L-Ultimate Filter 3nm 2 inch

Optolong L-Ultimate Filter 3nm 2 inch: 3 nm dual-band, the pinnacle of the L-series

The L-Ultimate is Optolong's narrowest and most advanced dual-band filter: 3 nm passband on both the H-alpha line (656.3 nm) and the OIII line (500.7 nm). Virtually all other light, from streetlights to moonlight and skyglow, is blocked.

With this bandwidth, you can photograph emission nebulae with maximum contrast and signal-to-noise ratio, even from downtown. The filter is also optimized against halos: the image remains clean even around bright stars. The 2-inch version (M48) prevents vignetting on large sensors and fits into 2-inch filter holders and photographic adapters.

For the discerning image creator

Those who want to take their dual-band work to the highest level will arrive at 3 nm. However, the dark background and fine nebula structure that this filter delivers require precise focusing and a stable mount.

Technology

The optical glass is 1.85 mm thin, planoptically polished, and features multi-layer ion-assisted coatings for high transmission, temperature stability, and scratch resistance.

Featured accessories

A clear focus filter is practically indispensable at 3 nm for fast focusing; we are happy to provide that.

For whom yes and for whom no

• ✓ Advanced nebula photographers with color cameras
• ✓ Those photographing under Bortle 8 or 9 or in moonlight
• ✗ Beginners in nebelfotografie: de L-eNhance of L-eXtreme is toleranter en voordeliger
• ✗ Fast optics around f/2: consider the L-Para, which is optimized for this

Specifications

You can find more accessories for this merk at the Optolong merk page.