Baader Ultra-Narrowband H-alpha 3,5nm Filter

Images uploaded by Customers

Add Your Review with Images
Baader Ultra-Narrowband H-alpha 3,5nm Filter

Please choose product variant from dropdown below to see SKU number

€ 257.00 Price excl. German VAT tax (19%): € 215.97

Please choose product variant from dropdown below to see stock status  


  • Precision grade enforced H-alpha filter for f/10 to f/3.5 optical systems
  • Opens up the extremely narrow 3,5nm H-alpha world
  • This enforced contrast results in even fainter stars, providing more signal of faintest nebulae detail
  • Manufacturing such ultra-narrow filter does require extreme coating homogeneity and very high CWL precision, which these filters are designed for. CWL= Center-wavelength / FWHM= full width half maximum.

Note: In general this DeepSky Ultra-Narrowband H-alpha Filter is not suitable for solar observation. The Halfbandwidth of 3,5nm equals 35 Ångstroem, high-quality H-alpha solar filter from SolarSpectrum start at 0.8 Ångstroem. At favorable conditions experiments might still be possible, although at lesser quality. Read more about it (in german) here:

We explicity warn you to observe the sun with a 3.5nm H-alpha Filter. This may be possible with a camera, but under no circumstances with the naked eye. Due to eye safety reason we must generally advise against experiments of this kind.

* Required Fields

€ 257.00 Price excl. German VAT tax (19%): € 215.97

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)
Do all Baader narrowband filter both UV and IR as well? I am thinking of using them with a Full Spectrum DSLR. Thanks.
Question by: Jon on Nov 1, 2016 11:59:00 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've got filter set h-alpha,h-beta,sII,oIII for full frame ccd, when will arrive the filter size 1.25" for h-alpha 3.5nm?
Question by: Nazario Montuori on Apr 30, 2017 11:39:00 PM | 1 Answer(s)
I understand your 3.5nm Ha filter in 1.25" size will become available later this year. When will you produce 3.5nm filters of the same size in SII and OIII? Thank you.
Question by: Peter on Jul 3, 2017 10:44:35 PM | 1 Answer(s)
Are you developing a 36mm unmounted version of this filter?
Question by: Paul Tribe on Nov 30, 2017 2:43:00 PM | 1 Answer(s)
Hello, are all Baader narrowband filters parfocal? I mean could I use extreme narrowband filters like the Baader 3.5nm with normal narrowbands like the OIII 8.5nm and expect them to be parfocal?
Thanks in advance for your time and help!
Ilias Galanis.
Question by: ILIAS GALANIS on Feb 5, 2019 9:50:00 PM | 1 Answer(s)
Do you have any plans to make a 1.25" of this filter?
Thank you,
Elias Galanis.
Question by: Elias Galanis on Jan 24, 2018 3:18:00 PM | 1 Answer(s)
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:
1 review
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

1 Item(s)

Rüdiger 24/01/2019 25/01/201910:21
  • Rating:
Hervorragender Filter
Ich habe bis jetzt nur mit dem Ha 35nm gearbeitet. Nun wollte ich aber feinere Strukturen erfassen. Da aber der Ha 35nm doch sehr überlappend mit dem Rot-Filter ist, war ein Filterwechsel unausweichlich.
Nach langem Abwägen zwischen der 7nm und 3,5nm Variante, habe ich mich für den 3,5nm Filter entschieden - und ich habe es nicht bereut.
Da ein Bild mehr als 100 Worte sagt, anbei eine Testaufnahme, die ich in einer der wenigen wolkenlosen Nächte machen konnte (Bemerkenswert: Nahezu Vollmond in ca. 16 Grad Distanz):

Das einzige Problem, das mir aufgefallen ist, ist die tückische Erstellung von Flat-Frames. Ich verwende dazu eine LED Light-Box. Diese scheint jedoch in dem Frequenzband ausgesprochen schwach zu emittieren. Dadurch waren die Ha-Flats ausgesprochen schlecht (siehe dazu auch zweites Bild). Eventuell bringt hier eine Luminanzfolie bessere Ergebnisse.

Datum: 19.01.2019
Objekt: Rosettennebel, NGC2244
Teleskop: Explore Scientific Carbon 102mm / f702mm
Kamera: ATIK 16200, BIN2x2, -40 Grad
Subframe: Einzelaufnahme 600s mit Ha 3,5nm Filter
Bearbeitung: BIAS, Dark und Flat-Korrektur; Delinearisiert in Pixinsight
  • Gewohnt gute Baader Qualität
  • Keine negativen Erfahrungen bis jetzt
Show more comments (-1) Hide comments

1 Item(s)

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