OIII Filter

OIII Filter

  (4 Reviews)
✓ 2 year warranty


1x in stock shipped 1-2 working days

About this product

Model:  skywatcher_oiii_filter-2
Part Number:  20196

The O-III narrowband filter is specially designed for the observation of diffuse and planetary nebulae.

The O-III narrow band-pass filter isolates just the two doubly ionized oxygen lines (496 and 501nm) emitted by diffuse, planetary and extremely faint nebulae.

O-III filters are best suited to telescopes with 8" or larger apertures and can produce near-photographic views of the Veil, Ring, Dumbbell, Orion and many other nebulae. 

Effective under even heavily light-polluted skies!

Customer reviews

Average Rating (4 Reviews):  
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Rating (max 5):  
01 February 2024  | 

Have not had chance to use this yet, but must once again compliment FLO on excellent service - delivery in a day can't be faulted

Rating (max 5):  
OIII Filter
09 March 2022  | 

Excellent service as always from FLO

Rating (max 5):  
It works!
12 December 2012  | 

I have a 12" Skywatcher Flextube Dobsonian, which is generally considered to be an excellent instrument for deep sky observation. However, I had never been able to find certain objects, never mind observe them! Two of the objects in question were the Veil Nebula and the North American Nebula. On good nights I would scan back and forth searching for these objects that some people report seeing in 'much' smaller apertures. However, despite numerous attempts I was never able to see a thing. So I decided to give one of these filters a go, not really thinking it would make much difference... but it did!

Within 20 seconds I came across a distinct curve of nebulosity, which extended for twice the field of the 32mm plossl that I was using. I had finally found part of the Veil nebula and not only was it visible it was quite obvious and I could even make out a certain amount of ragged detail along the edges. A quick nudge of the scope and I had found the second of the two brightest parts. What a thrill! An accessory that really does make a difference

Enthused, I aimed the scope at where I judged the North American nebula to be and low and behold the field of view was filled with pale nebulosity. It didn't have the glorious coherence of Orion but I could move the scope to trace the outline. Couldn't fit the whole thing in the eyepiece, so now I'm thinking about the 2" version for my 40mm Aero!

Having found the Veil nebula once more I took the filter off to see how it looked without it and the nebula was barely visible. Yes, it was there, but I would never have spotted it without the filter.

Can't wait to try it out on other objects.

For me this filter made the difference between seeing the Veil Nebula and not. Very happy

Rating (max 5):  
Amazing value!
01 June 2011  | 

The Skywatcher OIII filter gives a wider bandpass than the very narrow Baader OIII, so the view is not so dark, and yet it still provides incredible contrast on the right targets, such as the Veil Nebula in Cygnus. I've seen that with an 80mm scope and this filter. Stars stay as distinct points, so it seems to have a good accurate surface.

I would recommend this filter very highly as it does the job as well as any, and at a very affordable price.


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