FREE SHIPPING ON MANY PRODUCTS

The Telescope Authority
Since 1947

View Shopping Cart

Your Cart is Empty

Optolong L-eXtreme Dual-band Filter - 1.25-inch

SKU : OL-L-EXTREME-1

- Read
  • Free Shipping

  • In Stock

Add to Wishlist

Got questions? Click for live chat

  • Dual-band light pollution filter - 1.25-inch size.
  • The L-eXtreme filter is dual-band that passes H-alpha and O-iii emission lines.
  • It isolates these two nebula emission lines so that the contrast and signal-to-noise ratio between nebulae were maximized.
  • These two elements (Hydrogen and Oxygen) factor greatly in the scientific exploration of life.

 

Product Details

  • Dual-band light pollution filter - 1.25-inch

    The advantage of the L-eXtreme filter is that there is no transmission between the H-beta and O-iii lines and there are also no nebula emission lines there. In this case, it isn't letting light pollution come through so it maximizes nebula signals and the sky background is made darker while imaging.

    The L-eXtreme filter should better isolate the emission lines and better protect from light pollution.

    L-eXtreme Introduction

    Optolong L-eXtreme is a two 7 nm bandpass filter which can be used with one-shot color cameras like DSLR's (digital SLR), and monochrome CCD cameras, it is also more suited for fast systems. The convenience and cost-effectiveness of this filter allows amateurs to image a rich emission nebula, even in bright, light pollution skies. Optolong believes the design of L-eXtreme filter would be a better choice for fast systems at a competitive price. It isolates the H-Alpha, and Oxygen III nebula emission lines so that the contrast and signal-to-noise ratio between nebulae were maximized. For people who are living in very light-polluted areas, or when the moon is out, the L-eXtreme will be a good filter.

    Unlike the L-eNhance filter which is a tri-band (transmits H-b, H-a, and O-iii), the L-eXtreme filter is dual-band that passes H-a and O-iii emission lines.

    Comparison of transmission lines of L-eXtreme, L-eNhance, and L-Pro:

    Optolong L-eXtreme Dual-band Filter - 1.25-inch-transmission-1

     

    Optolong L-eXtreme Dual-band Filter - 1.25-inch-transmission-02

     

    Optolong L-eXtreme Dual-band Filter - 1.25-inch-transmission-03Hydrogen 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 for the exploration of life.

    Therefore, we highlight H-a, H-b, O-iii, and O-ii, and reduce the signal of sulfur.

    Spectrum and Characteristic

    • Substrate: B270.
    • Thickness: 1.85 mm.
    • FWHM: O37 nm+Ha 7 nm.
    • Blocking range: 300 to 1000 nm.
    • Blocking depth: light pollution line blocking >99%.
    • Surface quality: 60/40.
    • Transmitted Wavefront RMS: λ/4.
    • Parallelism: 30s.

     

  • specifications

    BandpassMulti Bandpass
    Filter ShapeRound
    Filter Size1.25"
    Filter Thickness1.85 mm
    Filter TypeDual Band
    Filter TypeLight Pollution/City Light Suppression
    Free ShippingYes
  • included items

    • Dual-band light pollution filter - 1.25-inch size.
    • The L-eXtreme filter is dual-band that passes H-alpha and O-iii emission lines.
    • It isolates these two nebula emission lines so that the contrast and signal-to-noise ratio between nebulae were maximized.
    • These two elements (Hydrogen and Oxygen) factor greatly in the scientific exploration of life.

     

Product Reviews

Customer Reviews
5.0 Based on 2 Reviews
Write a Review Ask a Question
  • Reviews
  • Questions

Thank you for submitting a review!

Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Filter Reviews:
A
02/27/2021
Anonymous
United States United States
L extreme

Excellent filter! Amazing results easily. Highly recommend.

OPT Telescopes Optolong L-eXtreme Dual-band Filter - 1.25-inch Review
RS
02/25/2021
Roger S.
United States United States
Optolong L-eXtreme Dual-band Filter - 1.25-inch

Noticed the difference in light pollution rejection. Between the my other Dual-Band filter. Thor's Helmet was well defined thru this filter!