Astronomy Specialist



- +

The Antlia 3nm Pro Ultra Narrowband 36mm filter set includes the following items:
The new Antlia 3nm Pro Ultra Narrowband filters boost the contrast of emission nebulae and supernova remnants for professional results, even under a bright sky affected by light pollution. The 3nm band pass is only 1% of the entire visible spectrum increasing the signal to noise ratio delivering high contrast images and extremely dark backgrounds. To even further enhance the contrast, and suppress the stray light and internal reflections, Antlia applies edge-blackening coating on each filter.

The maximum transmission is 85% - 90% and the transmission off band is only 0.001%. This is a value often undisclosed by other filter producers although it is critical to darken the sky background and minimise the halos around the stars. Blue-shift data shows that Antlia 3nm Pro filters can be used with nearly all systems as fast as f/3 with minimal loss in emission signal and meets the requirements of fast optics like Hyperstar and RASA.
Every filter is individually tested to ensure high the high quality standard that these filters have to meet end specifically the uniform thickness of the filter that deviate n more than ±0.05 from specifications.
Each filter cuts off the ultraviolet and infrared light so there is no need to use the IR-cut filter.

DO NOT LOOK AT THE SUN WITH THE ANTLIA FILTERS. Serious eye damage will occur.


Passing band 3 nm (FWHM)
Glass thickness 2.0 mm ±0.05
Optical flatness 1/4 λ (wavefront)
Bandpass transmission 85% - 90%
Off-band transmission <0.001% (OD5) @ 300-1000 nm
Coating Double-sided multilayer nano-coating
Surface quality 60/40 (in accordance with US military watch MIL-O-13830)
Parallelism 30"
Glass type Schott monolithic optical substrate (non glued)
Filter options Mounted 1.25", 2", Unmounted 36mm


Seagull Nebula by Robert Theunissen | APM LZOS 130/780, ZWO ASI2600MM Pro, Antlia 3.5nm & 3nm Ha, OIII & SII, iOptron CEM40   Seagull Nebula by Robert Theunissen | APM LZOS 130/780, ZWO ASI2600MM Pro, Antlia 3.5nm & 3nm Ha, OIII & SII, iOptron CEM40


Tarantula Nebula - QHY268M with Antlia 3nm Pro H-alpha & OIII filters by Caleb Kam


Tarantula Nebula - QHY268M with Antlia 3nm Pro H-alpha & OIII filters by Caleb Kam.


Crescent Nebula (NGC 6888) taken with Antlia filters by Andrea Maggi.



Carina Nebula by Stefano Salvi | SkyWatcher Quattro 200 f/4, Saxon AZ-EQ6, QHY268M Pro, Antlia 3nm SHO Ultra Narrowband filters, Prima Luce Lab Sesto Senso 2.


Customer Reviews

Based on 1 review
Ross D.
I love my Antlia NB filters!

In short, in my view these are the best value narrowband filters money can buy. I compared the Ha against a popular entry-level 7nm Ha filter and was very impressed with the greater clarity and contrast through the Antlia 3.5nm. These filters really allow you to get the best out of your mono camera, not to mention opening up the possibilities of shooting in less than ideal light conditions, such as a full Moon. There is some haloing around bright stars like Alnitak, but Antlia are very upfront about this and honestly it is better than I encountered with another Ha filter, so I have zero regrets or complaints.

The filters come very well packaged and protected, and you get the sense that they really care about their product and are not cutting corners, despite the very attractive pricing for these filters. I am so happy with them that I have since replaced my LRGB filters with a set of Antlias as well. If you're wanting to get into narrowband astrophotography and are hoping for a set of filters that will set you up for a long time without breaking the bank, seriously consider the 3.5nm Antlia set.

A note for users of the 294 sensor cameras (ASI294MM / QHY294M) - this sensor reacts weirdly when taking flats with Ha and S filters - do some quick googling and you'll confirm that it's your sensor, not the Antlia filters as it happens with all Ha and S narrowband filters. They do calibrate out just fine, you just need to be careful and precise when taking your flats.

Here are my first two narrowband images shot with these filters, NGC3342 and IC4628. Both shot on the ASI294MM-Pro from my Bortle 5 back yard in Eltham, Melbourne.

Welcome Newcomer