Optolong L-eNhance Filter 1.25" & 2"
The Optolong L eNhance is a dual band narrowband filter designed specifically for astrophotography of emission nebulae under light polluted skies. It transmits Hydrogen Alpha and Oxygen III wavelengths with very high efficiency while aggressively blocking artificial light. This gives you images with dramatic contrast, richer nebula structure and cleaner background with very little post processing work.
This filter is especially effective for nebula targets captured using color CMOS cameras, One Shot Color (OSC) cameras, and DSLR or mirrorless systems. Unlike broadband filters, it isolates natural emission lines while suppressing everything else, giving you a crisp signal to noise ratio that would normally only be possible from dark sky sites.
What makes the L eNhance special
Dual band pass isolates Ha at 656 nm and OIII at 495.9 and 500.7 nm
Excellent rejection of mercury and sodium contamination from urban lighting
Star colors remain controlled with minimal haloing or scattering
Ideal when you want narrowband results using a single OSC camera
Optical and Physical Specifications
Substrate: B270 optical glass
Thickness: 1.85 mm
Transmission: Peak above 90 percent at Ha and OIII
Blocking range: 300 to 1000 nm
Blocking depth: Light pollution line blocking above 99 percent
Surface quality: 60 to 40
Transmitted wavefront RMS: Lambda by 4
Parallelism: 30 seconds
Performance and telescope compatibility
Works with fast and slow optical systems from f2 to f10
Suitable for refractors, Newtonians and Schmidt Cassegrains
Perfect for deep sky imaging with OSC, DSLR, mirrorless or cooled CMOS
Reduces color gradients in city skies
Shorter exposure times than traditional broadband filters
The L eNhance gives you narrowband level contrast using standard color cameras, making it one of the most efficient upgrades for urban areas astrophotography.
