Optolong L-eNhance Filter - 1.25"

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 1.25" Filter provides an economical and practical solution for amateurs. It is a dual-band pass filter which has been designed for color CMOS and monochrome CCD 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. Optolong believes 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.

Hydrogen is the largest, the most primitive, the simplest, and the oldest element in the universe. Scientists consider that Hydrogen amounts to more than 90% of visible substance in space. Our sun is 5 billion years old, but so far hydrogen is still the key matter of nuclear fusion. While the sulfur element does not have much scientific significance, so keeping H and O is meaning for exploration of life. Therefore, we highlight H-a, H-b, O3 and O2, and reduce the signal of sulfur.

 Technical Data

• Substrate:  B270
  
• Thickness:  1.85 mm
  
• Surface Quality: 60/40 (Refer to MIL-O-13830)
  
• Fine-optically polished to ensure accurate 1/4 wavefront and < 30 seconds parallelism over the both surfaces
  
• Tpeak:  T>90%
  
• Blocking Range:  300 nm - 1000 nm
  
• Blocking Depth:  Light pollution line blocking >99%
  
• Parallelism: 30s
  
• Multi-layers of anti-reflection coating