O-III Filters For Visual Observing...

[Guest]

I read that O-III filters can help with certain nebulae whilst visually observing.  What type and price should I be looking at and do have you any recommendations?

[John]

I have the Lumicon and the Astronomik O-III filters (one is 2 inch and the other 1.25 inch) and can heartily recommend them.

I have not used lower cost ones so I can't really comment on those. I have used lower cost UHC filters though and generally found them to be less effective than more expensive ones so I suspect that filters are one area where spending a bit more does deliver noticeably better results.

The new Tele Vue Bandmate II O-III filters seem to be developing a really good reputation as top performers as well. Again not a budget option though:

https://www.firstlightoptics.com/televue-filters/tele-vue-bandmate-oiii-filter.html

 

[Jiggy 67]

33 minutes ago, John said:

The new Tele Vue Bandmate II O-III filters seem to be developing a really good reputation as top performers as well.

Reading the FLO description, this filter is made by Astronomik for Tele Vue....which is a fantastic endorsement of Astronomik by TV. I have Astronomik O-III and UHC and can totally recommend them. I’m no expert though.......but Tele Vue are

[Pete Presland]

I have the Baader 0-111 filter, very pleased with every time i have used it. I also own an explore scientific UHC filter which gives a slightly brighter view but less of a contrasty view depending on what object you are looking at.

I found this very interesting reading when i was deciding what filters i might require.

https://www.prairieastronomyclub.org/filter-performance-comparisons-for-some-common-nebulae/

[Rob_UK_SE]

I echo everything that has been said already about the Astronomik and Baader filters. I currently use the Astronomik one, but owned the Baader before that.

My only suggestion is on the basis that you will -probably- use an OIII more frequently with lower to medium power eyepieces. I would therefore very much recommend investing in a 2” model - assuming your lower power eyepieces have 2” barrels. For me, the Veil nebula was my main motivation for justifying the 2” model and I have not been disappointed with its performance. The filter is used every session in the summer months (for both parts of the Veil and M27, in particular). It‘s utilised for different targets in the winter such as M97. Even good ol’ Orion takes on quite a different character and nebulosity when observed through an OIII filter.

Edited August 24, 2020 by Rob_UK_SE
Typo

[callisto]

So correct me if I'm wrong.......The advice would be to spend more on the Astronomik/Lumicon filters etc, and stay away from the likes of the OVL/SW ones?

[Rob_UK_SE]

If a budget allows for it, the Astronomik and Tele Vue filters are superb and will show both greater nebulosity and tighter stars. The Baader is close, but -for me- the contrast wasn’t quite as good (albeit very close). However, all of these premium filters are rather expensive and require sufficient aperture to make the most of them.

Personally, I wish that I had been able to invest in premium filters from the start as it would have been cheaper in the long run, but I do also appreciate that this is not always possible.

Edited August 24, 2020 by Rob_UK_SE

[bish]

My baader OIII means I can make out the veil in my very light polluted back garden. No chance without it . Of course under a dark sky it really pops out.

[markse68]

1 hour ago, bish said:

My baader OIII means I can make out the veil in my very light polluted back garden. No chance without it . Of course under a dark sky it really pops out.

What aperture scope are you using to see it from Dudley Bish? It still eludes me from my similar bortle skies here in London with my 8.75” 

Edited August 24, 2020 by markse68
autocorrect 🤦‍♂️

[Stu]

20 minutes ago, markse68 said:

What aperture scope are you using to see it from Dudley Bush? It still eludes me from my similar bortle skies here in London with my 8.75” 

May be doable on a very transparent night Mark. I got it from here a few nights back with my 150p and a Lumicon filter. My skies were as good as it gets from here ie Mag 5, better end of Bortle 7. What are your skies like?

[markse68]

21 minutes ago, Stu said:

May be doable on a very transparent night Mark. I got it from here a few nights back with my 150p and a Lumicon filter. My skies were as good as it gets from here ie Mag 5, better end of Bortle 7. What are your skies like?

to be honest Stu I have no idea- nor how to judge. Do you just look for known mag stars and see if you can see them? I think the skies are definitely better than last year “thanks” to covid but i’ve had no luck so far. I’ve been taking my scope down to surrey when i visit my mum past few times but of course its been cloudy every time 🤦‍♂️ I thought we must have similar skies but I guess i’m a bit more central than you

[Stu]

1 minute ago, markse68 said:

to be honest Stu I have no idea- nor how to judge. Do you just look for known mag stars and see if you can see them? I think the skies are definitely better than last year “thanks” to covid but i’ve had no luck so far. I’ve been taking my scope down to surrey when i visit my mum past few times but of course its been cloudy every time 🤦‍♂️ I thought we must have similar skies but I guess i’m a bit more central than you

I normally judge by Ursa Minor, if I can see all seven main stars then I’m at Mag 5. I did think it may have gone a little fainter with averted vision but think Mag 5 is probably accurate.

Whereabouts are you?

I definitely think things are better this year with fewer flights and less pollution.

[markse68]

8 minutes ago, Stu said:

Whereabouts are you?

Not far from Greenwich. I don’t think i’ve ever seen Ursa Minor 😳😂 I shall have to look for it!

Edited August 24, 2020 by markse68

[jetstream]

My new Televue OIII beats a very good sample of an older Lumicon.

[Guest]

12 hours ago, Rob_UK_SE said:

I echo everything that has been said already about the Astronomik and Baader filters. I currently use the Astronomik one, but owned the Baader before that.

My only suggestion is on the basis that you will -probably- use an OIII more frequently with lower to medium power eyepieces. I would therefore very much recommend investing in a 2” model - assuming your lower power eyepieces have 2” barrels. For me, the Veil nebula was my main motivation for justifying the 2” model and I have not been disappointed with its performance. The filter is used every session in the summer months (for both parts of the Veil and M27, in particular). It‘s utilised for different targets in the winter such as M97. Even good ol’ Orion takes on quite a different character and nebulosity when observed through an OIII filter.

I'm using a cheap SW 28mm 2" LET eyepiece with my 200P.  I'll look into the various suggestions, but can't promise getting one given the prices for 2" versions...

[Waldemar]

Buy once, cry once... when the crying of the high prices is over, a big smile will lighten up your face!

[des anderson]

I use the Astonomik o-111 filter and UHC filter with my 9.25 sct, there just brill at bringing out that detail in nebula`s and the Veil mind blowing. Des 

[bish]

15 hours ago, markse68 said:

What aperture scope are you using to see it from Dudley Bish? It still eludes me from my similar bortle skies here in London with my 8.75” 

I am using a 10" scope. The conditions need to be very good too.

[jetstream]

4 hours ago, merlin100 said:

I'm using a cheap SW 28mm 2" LET eyepiece with my 200P.  I'll look into the various suggestions, but can't promise getting one given the prices for 2" versions...

I highly recommend the 2" filter as well. Your eyepiece is fine for viewing the Veil- our 25mm Super Plossl shows the Veil nicely in the H130.

Advice: buy the recommended filters mentioned here (Astronomik/Televue)- I have blown many dollars experimenting.....many ...200 USD on an unuseable Lumicon when they were in transition and...

Edited August 25, 2020 by jetstream

[jetstream]

18 hours ago, Rob_UK_SE said:

I currently use the Astronomik one, but owned the Baader before that.

I've heard the Baader OIII provides a very tight (one line) filter and with largely varying transmission levels. For some reason I find that filters need high transmission levels and is really noticeable eventhough the math and physics guys say the levels of differences involved can't make much difference. Capturing the second OIII line with a tight FWHM filter gives superiors views given high transmission IMHO.

Edited August 25, 2020 by jetstream

[John]

My skies must be better than I think. I can get the E & W Veil with my 4 inch fracs quite easily even with a UHC filter. I have glimpsed the brightest section (eastern segment) with 11x70 binoculars (unfiltered) on one of the best nights I can remember here. With my 12 inch dob and the Lumicon O-III (one of the earlier good ones ) the detail in the segments of the Veil is outstanding.

It is worth checking out the transmission charts of filters - there are a bunch of independant tests somewhere on line which tell all sorts of interesting stories.

Of my two O-III's I reckon my Lumicon is a touch better than my Astronomik especially in my 12 inch dob but both are really effective tools

 

 

 

 

[Pixies]

So is it ?:

New Televue Bandmate Oiii > old Lumicron Oiii > Astronomik Oiii > Latest Lumicron Oiii > Baader Oiii > 'transition' Lumicron Oiii

 

[bingevader]

18 hours ago, callisto said:

So correct me if I'm wrong.......The advice would be to spend more on the Astronomik/Lumicon filters etc, and stay away from the likes of the OVL/SW ones?

If your budget doesn't stretch that far and 'staying away' would mean not having one, then I would say no, get the others.

5 hours ago, merlin100 said:

I'm using a cheap SW 28mm 2" LET eyepiece with my 200P.  I'll look into the various suggestions, but can't promise getting one given the prices for 2" versions...

I have the 2" ES UHC filter and use it successfully! I intend putting the 2" ES Olll filter on the Christmas list at some point in the future.

[Stu]

2 hours ago, John said:

My skies must be better than I think. I can get the E & W Veil with my 4 inch fracs quite easily even with a UHC filter

I do think they are John! You’ve seen the Horsey from home haven’t you? I guess your NELM is somewhere between 5.5 and 6 perhaps? My skies are Mag 5 at best and I do think good skies kick in about 5.5 above above.

Skies are certainly better here than they were before lockdown, largely in terms of transparency which really helps with these objects as you know.

I’ll have a go with the 4” next times the skies look decent, whenever that may be....

[Mark at Beaufort]

I currently use an Astronomik O-III filter plus a TeleVue Bandwidth type 2 UHC and I also have a Lumicon UHC.

However, in saying that I have a Castell 2" O-III filter which I bought from 365Astronomy and its very good. I would recommend this filter if you can't afford the more expensive products.

I am hopeful we can arrange a StarGaZine talk covering visual filters O-III, UHC and H.Beta and discuss their bandwidth, transmission charts and the best objects for the various types.

If you want more information on seeing and transparency have a look at StarGaZine EP5 which is on YouTube. In that video I explain Ursa Minor and the different levels of transparency to judge your local situation.