UHC or OIII filter for visual use?

[ScottS]

I have been considering buying a filter for observing DSO's for a while now. I'm not entirely sure which one of these would see more use as an "all rounder", ie, one I would get most use out of?

Also, will they work with my Starguider EP's, and do they help at all with LP? I guess they would be put to best use at a dark site anyway.

Any suggestions/advice welcome.

Thanks.

[g0ibi]

1. UHC

2.OIII

If you look on the internet there are various lists of DSO's and the best filter to use..

Cheers

Ron

[ScottS]

Ok. Thanks. I'll have a look.

[John]

The UHC filter is the most versatile but the O-III is more effective on some objects. Most folks get a UHC first then add an O-III in due course.

These filters don't really help with LP but will enhance the contrast of nebulae even when there is some LP around. They work even better under dark skies of course !

Nebulae are the objects that benefit, rather than galaxies and clusters and some nebulae respond more than others.

[kerrylewis]

This is a very useful link that I found via his forum :http://www.prairieastronomyclub.org/resources/by-dave-knisely/filter-performance-comparisons-for-some-common-nebulae/

[ScottS]

This is a very useful link that I found via his forum :http://www.prairieastronomyclub.org/resources/by-dave-knisely/filter-performance-comparisons-for-some-common-nebulae/

Excellent! Thankyou. Looks like a UHC filter to begin with then.

I take it there will be no problem using this filter with my Starguider EP's then? I only ask as I've not used a filter before and haven't seen how they fit.

[AstroJOE]

As above. Having already researched this quite a bit myself my next purchase is going to be a UHC filter.....

I don't have your eyepiece but is it threaded for a filter at the bottom? If it is then it should accept filters. Assuming its a 1.25" ep make sure you get the correct size filter as well!

[ScottS]

Yes they are threaded in the barrel. I didn't think it would have been a problem as I've not seen it mentioned on here before and they are very popular EP's, but it's just one of those silly questions that, had I not asked, would have been an issue.

Thanks for the advice.

[mountainmadman]

Hi Scott,

I'm looking at exactly the same thing for my Skywatcher 150p and have decided on the UHC first.  Astro Baby has done an excellent write up comparing the two skywatcher filter models with each other.  http://www.astro-baby.com/reviews/O111%20and%20UHC%20filters/O111%20and%20UHC%20Filter%20Review.htm

By the look of it, FLO are out o stock of the 1.25" sizes at the moment.  I also have a half set of BST Starguiders in which I intend to use the filter.  I have had on loan from a work colleague the Baader UHC filter to use with my BSTs and it fitted fine.  Working on that basis, I assume the threads are the same on the both filter brands.

Hope this helps,

Tony

[crashtestdummy]

I have both but I would always advise the UHC first or as an only one if you don't want both

[ScottS]

Ok. That's great. Thankyou all.

[Pig]

Scott,

I have a 1.25" Lumicon UHC filter, it works a lot better on my 9.25" scope than it did on my 6" scope.

In fact I almost sold it when I had the smaller aperture scope as there wasn't much difference with or without it.

You may want to consider this before buying one.

[Moonshane]

I'm the other way around. If I could only have one it would be the Oiii. this reveals things not visible without it where the UHC enhances things you can already see. if you can, get both. I use my UHC pretty much only on the Orion Nebula on whih it is superb. My Oiii I use mainly on things like the Veil, North America Neb and the Crescent which are pretty much invisible without the Oiii

[Pig]

Is there any particular brand Shane that you could recommend ?

[John]

Is there any particular brand Shane that you could recommend ?

I'll be interested to hear Shanes opinion too but you already have a Lumicon UHC so a Lumicon O-III would compliment that excellently I would think.

Lumicon and Astronomik are just about as good as filters get IMHO. Not budget items of course but great quality and with a reputation with astronomers around the world to match.

[RikM]

I use my UHC a lot more than my OIII. The UHC seems to allow you to see a larger area of the nebulosity. The OIII shows more contrast and structure in the darker areas. Since I observe from a housing estate, I have quite a bit of light pollution to contend with. The main thing this hinders seems to be my dark adaptation, so that could be one reason why I favour the UHC. My OIII is from SkyWatcher, while my UHC is from Astronomik but I am not convinced that any potential difference in 'quality' is affecting which filter I use the most.

[Tiki]

Scott,

I have a 1.25" Lumicon UHC filter, it works a lot better on my 9.25" scope than it did on my 6" scope.

Mine works great with my 4" refractor.

... If I could only have one it would be the Oiii. this reveals things not visible without it where the UHC enhances things you can already see. if you can, get both.

Funnily enough, I find my that with my UHC I can just about make out a fragment of the California Nebula but with the OIII I can't see anything. (4" aperture though).

Hi Scott, I think it makes little difference as to which filter to star with, it is a close decision and almost everyone has a different take on the subject. Perhaps you should buy one s/h and see which filter lady-luck sends your way. The worst case scenario is that you lose the postage cost in the event of you deciding to re-sell. Filters are a lot of fun and bring a lot of objects within your eyeball's grasp.

[Pig]

I'll be interested to hear Shanes opinion too but you already have a Lumicon UHC so a Lumicon O-III would compliment that excellently I would think.

Lumicon and Astronomik are just about as good as filters get IMHO. Not budget items of course but great quality and with a reputation with astronomers around the world to match.

After looking at the case mine came in (SH) I am not sure what I have now.

On the font of the case its labelled with:-

Hydrogen -Beta 486nm (91%)

Oxygen III 496nm (93%)

Oxygen III 501nm (90%)

Hydrogen-Alpha 656nm

On the rear of the case its labelled with:-

Lumicon UHC filter

The actual etching on the edge of the filter itself is:-

Lumicon UHC

[Moonshane]

hi john et al. My UHC and Oiii filters are both Castell and I really rate them for quality and value for money; I do understand that their QC is possibly variable though as others have reported not so good results.

I am hoping to compare my filters with Astronomik or Lumicon at future star parties and then I can decide whether to 'upgrade'. If I do it will be to Astronomik I think at this stage.

I also have a Skywatcher Hb filter but am yet to use this in anger really. Also, I'll be trying this at SGL's star party for sure.

[Stu]

Having just purchased a Lumicon OIII can say that it does appear to be a significant improvement over the SW filter, as you would expect for the price.

The bandpass is very narrow, but even in a 76mm scope it allowed me to see the Veil from average skies where the SW didn't with this scope. From what I have read, the OIII does have clear benefits for the veil, and a few other objects which makes it worthwhile for me. The UHC is useable on a much wider range of objects and will probably show more nebulosity on objects like M42 in my scopes. It is due in a few weeks so will report then.

Stu

[estwing]

I have the astronomik 2" UHC and I have yet to use it on my dob..

[Tiki]

I have the astronomik 2" UHC and I have yet to use it on my dob..

Why not? Is it that you can see it all anyway with your 18 incher?

[ScottS]

Ok. Well I think I will go for the UHC first, find a dark sky, and see how I get on with that.

Thanks again everyone.