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Optolong L-eXtreme Dual-band Filter - 2-inch

SKU : OL-L-EXTREME-2

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  • Dual-band light pollution filter - 2-inch.
  • 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 - 2-inch

    The advantage of the L-eXtreme filter is that there is no transmission between the H-beta and OIII 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 7nm 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 - 2-inch-transmission-01

    Optolong L-eXtreme Dual-band Filter - 2-inch-transmission-02

    Optolong L-eXtreme Dual-band Filter - 2-inch-transmission-03

    You can also view this charts in greater detail in the Gallery tab, click on the thumbnails for each image.

    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 for the exploration of life.

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

    Spectrum and Characteristic

    • Substrate: B270.
    • Thickness: 1.85mm.
    • FWHM: O37nm+Ha 7nm.
    • Blocking range: 300 to 1000nm.
    • Blocking depth: light pollution line blocking >99%.
    • Surface quality: 60/40.
    • Transmitted Wavefront RMS: λ/4.
    • Parallelism: 30s.

     

  • specifications

    BandpassMulti Bandpass
    Filter ShapeRound
    Filter Size2"
    Filter Thickness1.85mm
    Filter TypeDual Band
    Filter TypeLight Pollution/City Light Suppression
    Free ShippingYes
  • included items

    • Dual-band light pollution filter - 2-inch.
    • 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
4.9 Based on 15 Reviews
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Filter Reviews:
RN
10/12/2021
Ryan N.
United States United States
Amazing Filter!

Before using this filter I used to always have to push the color saturation in my images but not anymore. I haven't boosted color saturation at all with filter, the colors already come out so vivid! The design of this filter is great. I have a RedCat, which was super easy to mount this filter onto, just screws right in. Just required a little change in focus and I was off and imaging.

OPT Telescopes Optolong L-eXtreme Dual-band Filter - 2-inch ReviewOPT Telescopes Optolong L-eXtreme Dual-band Filter - 2-inch Review
RS
10/11/2021
Richard S.
United States United States
Made narrowband work so much easier

I had started out with separate Ha and OIII filters for use with my One Shot Color camera, but quickly tired of the extra exposure time and nuisance of aligning images. Also the overall cost of the separate filters was more than the expense of the single dual narrowband L-eXtreme filter. Wished I hadn't wasted the money and just bought the L-eXtreme filter in the first place!

OPT Telescopes Optolong L-eXtreme Dual-band Filter - 2-inch Review
RB
09/29/2021
Rick B.
United States United States
L-eXtreme Filter

I've had a chance between the clouds to use the L-eXtreme with my Zwo 533 Pro and WO 73. I was very happy with the mages of the heart and soul nebula under 98% moon. 4 minute subs. I'm fortunate to shoot under bortle 1-2 skies. I'm very happy with the results.

JF
09/16/2021
Joe F.
United States United States
Fantastic

The first DSO, I used it on was the Dumbell Nebula, and I was shocked exponentially. I am not tech savvy but only know that in my Bortle 7 skies, the Dumbell was so detailed and brightly colored that it looked better than any image I took in Bortle 1, 2, or 3 skies. So I give a 10 star on a 5 star scale. I will know more about Extreme as time goes on, but for now, I see where the performance far outweighs the cost. Extreme is the only filter I have ever used with this unimaginable performance experience. THANKS!!

RG
06/29/2021
RICK G.
Excellent filter

Excellent filter in the duo bandpass. Cuts through light pollution and gathers amazing bandwidth from DSO targets. HIGHLY recommend...single 10 minute exposure of the Cygnus loop, Redcat51 with ASI294MC Pro and L-Extreme filter

OPT Telescopes Optolong L-eXtreme Dual-band Filter - 2-inch Review
WC
06/24/2021
William C.
United States United States
No Greasy Filters!

I gave up using this excellent 2"filter in my Radian 61 filter well and had it reset in a Canon Drop-In Filter. Now I can use the filter without greasy finger smears and use in several other lenses.