View Full Version here: : UHC Filters

John Saunders
11-06-2007, 12:43 PM
Hi folks.

I'm looking for advice from the great sages of astronomical wisdom...

I want to buy a UHC filter, don't want to pay the earth for it, but don't want rubbish either. Can somebody/s give me the benefit of their experience and tell me which brands are quality but are not going to bust the bank.

Brands I have come across are the Baader, Astronomiks, Lumicon.

I await the wisdom to flow from your keyboards!



11-06-2007, 12:54 PM
I had the Baader UHC 1.25" version. Used it with a 22mm Televue panoptic on my old 12" GSO dob - can't say I was that impressed with it.
Reviewers say that that model isn't as harsh a filter as some others, letting a bit more light through. But, the lack of an obvious WOW factor with the filter in place made me put it up for sale.
I've also had a look through a 13mm nagler and Lumicon UHC filter in a 10" GSO dob and that was awesome:eyepop: Dramatic contrast, beautiful increase in nebula detail on Eta C as I remember.
Have I confused you further!? Sorry:whistle:

11-06-2007, 02:34 PM

Your question is one that can inspire lots of debate...for me the two at the top of the heap in terms of quality/performance are the Astronomiks (available at Bintel...I think they are on sale at the moment) and the NPB Filter from DGM Optics (sold by Omega Optical in the US and they will ship overseas)


from their website***
NPB 1.25" – DGM Optics™ Nebula Astronomy Filter (price USD$75)

The NPB (Narrow Pass Band) filter is an Ultra High Contrast type of filter that is very effective for small and fainter emission and planetary nebula and a variety of bright nebula, especially through larger scopes

I have owned the Astronomiks and the DGM and for me when compared side by side I preferred the DGM (just barely)...On my scopes and to my eye it seemed to pull out just a hint more nebulosity...admittedly there was not much between them to my eyes.

I have not owned but I have looked on a few occassions through other brands of UHC filter and I'd stack the DGM Optics #1 and the Astronomiks a very close #2...then everything else

Although I have not tried one myself, I have read that the Orion Ultrablock (also avaialble at Bintel I think) is also a good performer.

I would likely rank other types of filters differently (OIII etc.) but for the "UHC" kind I'd place them that way...

Just my limited opinion...good luck!

11-06-2007, 02:36 PM
I have a Lumicon UHC 2inch and it`s great.
For the money I reckon it`s one of the best out there.
The Astronomik is quite pricey, not sure if the extra dough is worth it???, that`s why I went Lumicon, and good reputation.
The Lumicon has high transmission properties and still turns up the contrast well.
Frontier Optics have em for $150 1.25inch and $275 for 2inch.

Hope this helps,

11-06-2007, 06:33 PM
keep in mind that the filter is only enhancing what is already there by removing some of the skyglow, i have the Baader UHC-S/O-III.
as far as im aware the baader uhc-s is a lot more forgiving than a lot of other uhc's making it usable in smaller scopes. i can say that yes it makes a large difference on SOME nebulae and others it seems to do not much at all, if your scope is 8"+ id probably be looking for an O-III filter which dramatically improves contrast but you will start to lose stars in smaller scopes.
usually the first filter i reach for is the O-III :)

John Saunders
11-06-2007, 07:06 PM
Thanks for the feedback. My 'scope is an 8" Skywatcher Newt and I really would like to improve the viewing quality when I can't get out to good dark sky locations.

From what I've read it's a matter of preference - there are arguments for an against UHC or OIII. I just know I can get a 2nd hand UHC (there are a couple in the classifieds at the moment) and after my viewing early this morning over at Redcliffe I would like to get a filter that reduces the pollution and lifts the nebs a little.

Again, thanks for the feedback and if there are any more ideas or thoughts - type away I am all ears...and eyes...



11-06-2007, 08:16 PM
I used mine through my 8" f6 Skywatcher Newt. Performed great. I was using the Baader UHC-S 1.25" Fliter. The star colour is a pretty Terquoise but boy do the nebs stand out, seeing M42 through it in suburban areas is a real eye opener as is Eta etc... Only thing I cannot tell you is how it performed under dark skies. I have no idea I didn't get a chance to try it out. If I was more into visual Astronomy I would get that and the OIII apparently they make a nice pair to compare objects with. Good luck with your Choice.

11-06-2007, 09:33 PM

Checkout this link to CN. David Knisely, a well respected filter expert tests various UHC, OIII, H Beta etc filters on 90 or so nebs.
The UHC comes out on top as the best all round filter if you are thinking of buying just the one.

http://www.cloudynights.com/item.php?item_id=1520 (http://www.cloudynights.com/item.php?item_id=1520)


11-06-2007, 09:41 PM
John, the DGM Optics (Omega) NPB is the all round pick IMO, and it isn't that expensive. I also have at present a Baader UHC-S, and this works OK on smaller scopes, as it allows more light throughput, but the NPB is superior at bringing out nebulosity. Some kind people on these forums recommended to me, and they were right!

Clear skies

12-06-2007, 12:31 AM
I have a lot of filters including Astronomics OIII and UHC, DGM NPB, and several others. I have also used the Lumicon, Celestron, Orion, Televue and Thousand Oaks versions of these. Depending on the target and it's respective emission characteristics each filter can come out on top of the others, over a large range of targets. However, if I had to pick just "one" filter for an 8" newt it would be the DGM NPB filter. It offers a "good" improvement on a wider range of targets than any of the other filters I have used and it isn't all that expensive compared to some of them.

CS-John B

14-06-2007, 08:27 PM

I'm also looking at buying a filter to assist with nebulas etc. At the moment I am leaning towards the Lumicon filters and was planning on getting the UHC filter but now I've read that this is best for dark sky viewing and their Deep Sky filter is better for suburban observing (which is where I mostly observe from).

So now I'm getting more confused. Has anyone looked through both these filters? Is there much of a difference in performance, or does the dark vs suburban sky issue really affect which one to choose.



John Saunders
16-06-2007, 08:52 PM
Well, I have gone for the DGM NPB filter which I ordered direct from the States. Total cost has worked at $118 AUD...so now I await the arrival...next week before I head off on holidays...

Thanks all for the advice!

John :thumbsup: :thumbsup:

16-06-2007, 11:55 PM
John I have the NPB filter as well - you will not be sorry. My first view of the Carina Neb through it absolutely blew me away, as anyone who was within earshot at Ron's place that night will tell you.

17-06-2007, 10:26 AM
My first experience with filters was to have one for observing in light-polluted suburban backyard with my 200mm Saxon Dob..I chose a Sirius Optics C E 1 (Contrast Enhancment) broadband filter which made Star Clusters like 47 Tuc very bright and sharp!...I then progressed to a Saxon 254mm and then deceided for a Nebula/deepsky filter...I have found the Astronomik's UHC-E a great advantage when viewing bright Nebulae as well as the faint stuff..most of the stars appeared a faint soft blue with pink specks which allows the other wavelength's of light (O III, Ha, etc ) through..the Keyhole Nebula in Carina and the Trifid in Sagittarius is amazingly detailed when coupled with a 25mm EP!!!

17-06-2007, 11:04 AM
Can I ask a related question? I have been debating a UHC filter, but I was wondering just how much difference it will make to my views. Here in Mildura there isn't really any significant skyglow (light pollution is mainly, the neighbours security lights which apparently have to be set to shine into my backyard all night). However, there is a bit of dust in the air quite regularly. Would it really be worth my while getting one, especially as my EPs are all relatively cheap ones?

17-06-2007, 01:09 PM
What a uhc filter does is to darken the sky background by filtering out everything but a small band of wavelengths of light, which emission and planetary nebulae radiate in. If you cant get good dark adaptation for your eyes, the usefulness of a uhc filter will be limited.

What can help in such situation is to drape a cloth over your head to block any extraneous local light. I find this a help even at dark sites when viewing very faint objects.

17-06-2007, 01:44 PM
Thanks, actually by keeping my head below the fence line, I avoid any direct view of the neighbours lights, so dark adaptation isn't too bad. I shall try with a cloth over my head though - will help keep warm!

I was wondering more whether the UHC would improve contrast much with a fairly dark sky? For instance, when dark adapted I can see a small faint fuzz where the lagoon nebula is (dunno whether I'm seeing the nebula, the cluster, brighter patch of the milky way or imagining it, but I can use it to point the scope in the right place).

17-06-2007, 01:51 PM
The short answer is yes. Filters are just if not more effective at dark sites.
If your eyes are well dark adapted, the lagoon neb will be strikingly obvious when using a filter.

17-06-2007, 04:28 PM
I'm not explaining well enough again! I can see it fine in the scope, I meant I can see something in that area with the naked eye/averted vision - as an estimate of the dark skies.... sorry! Anyway, if a UHC is still useful I shall check them out with the links earlier in this discussion. Thanks.

17-06-2007, 04:53 PM
Sorry, no, it me not reading and comprehending properly :ashamed:

17-06-2007, 06:00 PM
Went to the Leyburn dark sky site for a night of observing on Friday night.
I was surprised at how much better my UHC performed compared with it`s performance in the backyard. I knew it would work better on a dark sky, but it just blew me away, especially on the Carina and Lagoon nebula and even the Tarantula nebula. Lots of other targets just stood out. First time I have viewed at a dark sky site since I have owned this filter.

19-06-2007, 01:04 PM

As Geoff indicated a Narrowband filter works best from dark skies as opposed to light polluted skies. If you already have good sky conditions you will get significant improvement on a lot of nebulous targets with a narrowband or UHC in your 10" dob.

The DGM NPB filter is a very narrow pass band, narrowband filter. It is almost a hybrid between a UHC and an OIII filter. I would recommend you consider this filter for use with your 10" dob.

CS-John B

John Saunders
21-06-2007, 11:11 AM
Tell you what, it's a quick mail-out from the US of A! My filter has arrived...at the same time as the lousey weather...dang! :( Hopefully there will be a little bit of clear sky before I head off on holidays with the family...and leave the scope behind at home. :P

The weather in Brissy the last two days reminds me of my last posting to Victoria - cold, cloudy, bleak, but...with the promise of snow in the high country. Unfortunately we don't have ready access to the snow in Brisbane...ahhhh, such is life...the ice skating rink is just down the road, though.