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Optolong 2" L-Enhance Tri Band Filter

In stock
can be shipped within 1-2 days

Price includes VAT, plus delivery

The relentless spread or urbanization and its associated light pollution have become a growing problem for all amateur astro photographers. The current solutions to the problem can be expensive and might include the purchase of a monochrome camera, several types of narrowband filters and a filter wheel.

The Optolong L-Enhance provides an economical and practical solution to this. It is a Tri-band pass filter which has been designed for DSLR (digital SLR), colour CMOS and monochrome cameras. The convenience and cost effectiveness of this filter allows amateurs to image a rich selection of astronomical images, even in bright, heavily light-polluted areas. The design of our L-Enhance filter is a technical innovation among filters. It effectively isolates the H-Alpha, H-Beta, and Oxygen III nebula emission lines and achieves a maximum transmission of up to 90%. The performance of this filter delivers images that superbly control the impact from light polluted skies.

Astrograph recommend this filter mainly for use with one shot colour (OSC) cameras. The filter has a broad coverage of H-Beta and OIII which means it will pass light to both the Green and Blue filtered photosites of a colour camera. Red is obviously covered by the H-Alpha bandpass. All other wavelengths are effectively blocked allowing far higher signal to noise than traditional light pollution filters.



Transmission peak:  T>90%
Blocking range: 300-1000nm
Blocking depth: light pollution  line blocking >99%
Surface quality: 60/40
Transmitted Wavefront RMS: λ/4
Parallelism: 30s

  • Thickness 2mm (add 0.7mm to the back focus specification of a corrector)

    Multi-layer anti-reflection coating

    Non-cementing optical substrate coating

    Optolong L-Pro filter adopts precision coating based on Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL(central wavelength) no deviation affected by temperature change.

    Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band.


Browse this category: Imaging Filters 2"