Baader 3.5 / 4nm f/2 Ultra-Highspeed Filter-Set – CMOS-optimized (H-alpha / O-III / S-II)

More Views

Images uploaded by Customers

Add Your Review with Images
Baader 3.5 / 4nm f/2 Ultra-Highspeed Filter-Set – CMOS-optimized (H-alpha / O-III / S-II)

Please choose product variant below to see price and SKU number

€ 735.00 Price excl. German VAT tax (19%): € 617.65

Please choose product variant below to see stock status  


  • Baader H-alpha / O-III / S-II f/2 Ultra-Highspeed Filter Set – Premium Grade
  • 3.5 / 4 nm FWHM (to harmonize the exposure time from H-alpha with O-III / S-II), recommended for extremely fast optical systems from f/3.4 to f/1.8
  • Specially designed for the special filter requirements when used with fast optics like the Celestron RASA astrographs
  • For highest contrast even at strongest light pollution, minimizes star size, emphasizes finest nebula detail – indispensable under Bortle 9/8/7/(6) skies
  • Reflex-Blocker™ hard coated and planeoptically polished – with sealed coating edges (Life-Coat™)
  • Blackened edges all around, with filter-lead-side-indicator in the form of a telescope-sided black outer rim
  • Optimized for modern CMOS cameras, but likewise excellent for CCD camera technologies

* Required Fields

€ 735.00 Price excl. German VAT tax (19%): € 617.65

Product Questions

Sort by ASC
What's the actual size of your 2" filters in "mm" with and without frame/ring? What step down adapter is suggested from a 52 mm to "-- mm"?
Question by: Waqas Ahmad on Oct 10, 2016 7:54:00 PM | 1 Answer(s)
What are the threads and pitch of your 1.25" and 2" filters?
Question by: Anders G. on Sep 20, 2017 12:55:00 PM | 1 Answer(s)
I'am using de 2" Ultra High Speed filters Ha, SII en OIII for my C14 Hyperstar. Can you tell me which side of the filter should point to the camera? Or does this not matter.
Question by: Edwin van der Sijde on Sep 18, 2021 11:03:00 AM | 1 Answer(s)
Hi, besides a telescope i am also using the following setup: Canon EOS Ra + Canon L series high speed lenses (from wide angle to 400mm). I own multiple 2" M48 (threaded) NB filters and want to expand this (2" mountable only).

Question: Do you offer / know a good solution to use my Baader 2" filter set in combination with the Ra+Canon lenses please?
Question by: Bert De Wilde on Nov 23, 2021 7:54:00 AM | 1 Answer(s)
What happen when i use this ultrfast narrowband filters recommended for F3,4-1,8 on a F4?
Question by: Jan on Dec 21, 2021 2:09:00 AM | 2 Answer(s)
I have the Celestron EdgeHD 11 and HyperStar v4. I already have a set of Baader 6.5nm Narrowband 2" CMOS Optimized filters, but they are not optimized for the f/1.8 I will get with HyperStar. What will really be the difference I see with the Ultra Highspeed filters compared with what I have?
Question by: Martin Cohen on Oct 25, 2021 5:11:00 PM | 1 Answer(s)
Are there downsides when using the 'ultra fast' filters with 'slower' sytems. For example if I were to use the ultra fast filters on an f7 system would there be any negative effects? (I have both fast and slow systems and was planning on buying the ultra fast set but only if I can also use them with the slower setups)
Question by: Michael on Jul 8, 2021 12:20:00 PM | 1 Answer(s)
What is the actual disadvantage of using these filters with a Kodak KAF 12600 CCD mono chip. What is the resistance of these filters, especially the OIII, to bright star hallows caused by fast optics.
Question by: Lynn on Aug 28, 2021 11:25:00 PM | 1 Answer(s)


This new generation of Baader CMOS-filters features:

CMOS-optimized Baader Filters
  • Increased contrast
  • Ever more narrow passbands
  • Reflex-Blocker coatings, for largest ever freedom from halos, even under most adverse conditions concerning aux-optics
  • FWHM on each filter category carefully designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio
  • Identical filter thickness to existing standards, with utmost care for parfocality
  • Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim, to additionally eliminate any reflection due to light falling onto the edge of a filter
  • Each filter coated individually, with sealed coating edge (NOT cut out of a larger plate with coatings left exposed, read more)
  • Life-Coat™: evermore hard coatings to enable a non-aging coating for life – even in a most adverse environment

  • Further information, test reviews, image results...

    Don´t be misled.

    These all new CMOS-optimized filters work magnificently with all existing digital camera technologies, be it CMOS or CCD. However – an owner of CCD-camera-technology will still find our previous, extremely affordable, narrowband filter technology to be fully apt for excellent imaging. But: "the Better always is enemy to the Good".

    ... can be found on our detailed Blogpost:

    Baader Blogpost:
    New CMOS-optimized Baader Filters

    Related Articles

    Additional Information

    Technical Data not yet specifiedPlease choose product variant from dropdown above to see technical data of your chosen product

    You may also be interested in the following product(s)

    Overall Average Rating:
    2 reviews
    5 star
    4 star
    3 star
    2 star
    1 star
    • Date - Newest First
    • Date - Newest First
    • Date - Latest First
    • Highest Rated
    • Lowest Rated
    • Most Helpful

    2 Item(s)

    Julian Shroff 323/11/2021 20/11/202111:22
    • Rating:
    New filters for a new era of narrowband imaging
    For a long time, imaging at F2 was sort of an RGB-only thing for me. But when I came upon the new Baader High Speed Ultra Narrowband F2 Filters, that changed. With the new ability to shoot narrowband targets at 3.5/4/4nm for Ha/Oiii/Sii respectively, this truly changed the way I view narrowband imaging.

    After thoroughly testing the new filters, I'm happy to say that they work just they way they are supposed to: They produce deep and clean images of narrowband targets with high-resolution CMOS cameras, while avoiding the common issues of F2 imaging such as reflections or halos.

    I have three sample images which were between 4 and 8 hours of integration time each with my RASA 8" and QHY183M Monochrome camera.
    • Everything, really. Affordable filters that produce very clean images. What more could we want? :)
    • -
    • Watch my video
    Show more comments (-5) Hide comments
    Maurice Toet 288/10/2021 16/10/202112:30
    • more than 1 year(s)
    • Rating:
    Ultra-Highspeed CMOS-optimized Narrowband Filters
    With these new Ultra-Highspeed filters Baader Planetarium indeed found their way. I use the Ha (3.5nm), OIII (4nm) and SII (4nm) in combination with a Takahashi Epsilon-180ED f/2.8 and ZWO ASI294MM Pro in severe light pollution (Bortle 8/9) from my garden observatory in The Netherlands. Here's an example of an SHO colour mapped image over approximataly 29 hours of integration time captured with this setup. Thanks to the new coating-technology of these CMOS-optimized filters, halos have become history.
    • Great value for money, excellent suitable for CMOS sensor thanks to new coating-technology
    • -
    Show more comments (-5) Hide comments

    2 Item(s)

    What kind of abuse are you reporting?
      Please, wait...