Fun with filters- a skeptic converted

[pyrasanth]

I was initially skeptical about the benefits of filters. I looked at M27 initially & under the light June sky saw only a splodge of light. I took the plunge a bought 2 moderately priced sykwatcher filters- a UHC & an OIII paying careful attention to the note that a 6" or greater aperture is required to capture enough light to make these filters beneficial.

I removed the 27mm 2" eyepiece and fumbling in the dark screwed in the OIII filter without cross threading (a very bad habit of mine on my DSLR). I was BLOWN away by the difference!- that splodge had become a clearly defined dumbell nebula like you see in a monochrome photograph. The difference was quite startling! I wonder what it will be like to use this filter under darker skies- I can't wait.

If you've not experienced these filters & have a telescope of suitable aperture they are well worth the investment. The question is does a really expensive version make any further difference?

[ronin]

What was the UHC one like if you tried it?

Only ask as on CN some months ago someone said that the one filter that was most worthwhile getting was the OIII one that you have mentioned and described.

It would be interesting to have an idea of the general accuracy of the CN post.

Equally don't have a scope of 6" aperture so could be utterly irrelevant.

[John]

They do make a difference on nebulae, particularly planetaries and supernova remnants

I've found both UHC and O-III filters useful and effective in all my scopes including the 4" and 4.7" refractors. 

Reading about it is one thing but seeing that difference for yourself is the best way 

[ScottS]

I was actually looking at M27 on Saturday night and completely forgot to try the Baader OIII that I had bought and was sitting in my box

[astronymonkey]

Hmmm , im never convinced with filters, although ive never tried the Olll or H-beta ones. I think the reason is the color cast that they give and ive even considered getting rid of my UHC as its never really used. I also need to get my head around the idea thqt getting rid of some of the light will improve the image.

I know some objects are meant to thrive on filters .. the veil for example.... but id like the chance to have a look through a scope, with and without just to see if they live up to the hype.

cheers

[John]

Hmmm , im never convinced with filters, although ive never tried the Olll or H-beta ones. I think the reason is the color cast that they give and ive even considered getting rid of my UHC as its never really used. I also need to get my head around the idea thqt getting rid of some of the light will improve the image.

I know some objects are meant to thrive on filters .. the veil for example.... but id like the chance to have a look through a scope, with and without just to see if they live up to the hype.

cheers

I know just what you mean and share your caution but there are a few objects (the Veil is one) where the difference with a good filter is like night and day. It can make the difference between seeing virtually nothing and seeing it really well. For just those objects the O-III earns it's keep with me.

Really - no hype at all and I've been just as skeptical as you are 

[swamp thing]

The question is does a really expensive version make any further difference?

Yes.

However the laws of diminished returns also sets in much as it does with eyepieces. I have the Lumicon O-III filter which is about as good as they get but is it worth the hefty price tag ????

To me, yes, but I spend a great deal of my observing time on diffuse nebulae. If I didn't I probably would use a budget one, in much the same way I don't buy orthos or plossls for planets as I don't really observe them and the expenditure for me just isn't viable.

If money is no problem go for it. If you are on a budget, consider how much time you would spend using it against the cost.

[Paul73]

Yes.

However the laws of diminished returns also sets in much as it does with eyepieces. I have the Lumicon O-III filter which is about as good as they get but is it worth the hefty price tag ????

Don't forget the second hand market. If someone has forked out for a premium filter, they will have looked after it. I bought second hand last week (Lumicon OIII) and paid about £20 more than a new mid range offering. It was immaculate and the views, based on its one outing, are fantastic.

Paul

[Paul73]

Here is an interesting thread on different filters and the Viel. Apparently you don't need a pricy OIII to see the thing! I had been labouring under this missaprehnsion and hadn't even bothered looking.

http://stargazerslounge.com/topic/219216-uhc-filters-and-the-veil/

Paul

[astronymonkey]

Ive seen the veil but never with a filter. Under a dark sky, with reasonable aperture it looked great so im not sure what more a filter would add. Hmmm

[NGC 1502]

It's often said that UHC filters are no use with a small scope.  

From Kelling Heath last Sept the Eastern Veil was no problem to see with my 70mm Pronto and a Skywatcher  UHC. The dimmer Western Veil was seen with a struggle. But I'd agree that the more aggressive OIII is not suited to such a modest aperture.

There's no doubt at all that used on the right objects and instrument, these filters do a great job.

Regards, Ed.

[John]

Ive seen the veil but never with a filter. Under a dark sky, with reasonable aperture it looked great so im not sure what more a filter would add. Hmmm

It's a pity it was so cloudy at the SGL star party this year - I had my Astronomik O-III with me and you could have had a go with it.

I've seen the Veil unfiltered too, even the E portion with 15x70 binoculars on one really good night last year, but the filter makes so much difference to this object, or group of objects, that I just have to use it. It's really not subtle at all - if I had to put a quantative value on the difference I'd say about 4x as bright and contrasty with the filter and wisps of nebulosity that are otherwise not visible can be traced quite clearly between the E & W Veil segments, if that makes any sense. 

Sorry to bang on about this but it's the best nebula viewing I've had in all my time in the hobby with this filter so I feel quite passionate about it

I'll stop it now as I really can't say any more.

[astronymonkey]

Hi john,

maybe an Olll is something I may add to my eyepiece case over summer.

I have thought sbout it but never took the plunge but given your strong recommendations I may have to .

I agree about sgl weather though , but at least we saw the sun for a few hrs.

cheers

[Moonshane]

I have Castell Oiii and UHC and intend one day to 'upgrade' to Astronomik. BUT I always find something else to spend my cash on that will benefit me more than the change as they are really great value and work very well. The Oiii is the one I'd keep but it's good to have both. The Veil is awesome at a dark site with the big dob and Oiii but I also saw it with a 130mm newt the other night. M42 is astounding with aperture and UHC even from home.

[LeeB]

I have a number of filters but use the lumicon uhc alot , as above the orion neb pops with it, with detail in the cloud really brought out. The return does decline with apeture but is still useful in the 4.5 inch tal.

[cutepetgroomer]

Sounds like I may have to purchase a new scope for the purchase of filters. Or just get a hybrid diagonal and 1.25 format eps at least but that sounds awesome

[pyrasanth]

What was the UHC one like if you tried it?

Only ask as on CN some months ago someone said that the one filter that was most worthwhile getting was the OIII one that you have mentioned and described.

It would be interesting to have an idea of the general accuracy of the CN post.

Equally don't have a scope of 6" aperture so could be utterly irrelevant.

I have 3 filters. A CLS, OIII & a UHC. The most significant observation that I noted was that the CLS seems to make very little difference under any of the objects I looked at. The UHC & the OIII on M27 gave very similar results but the seeing was not particularly brilliant so I need to do more tests on different objects to see if there are significant differences but in the interim I will stick out my neck & say both seemed to work well. The sky around M27 was jet black & the nebula stood out in glorious detail with the OIII filter.

[rwilkey]

Sounds like I may have to purchase a new scope for the purchase of filters. Or just get a hybrid diagonal and 1.25 format eps at least but that sounds awesome

Hi Cute', there are less aggressive filters that you can use with small apertures, the Baader UHC-S is an example, and I think Orion do a similar one called UHC-E, might be worth a go if you are interested in nebs?

[RikM]

If you've not experienced these filters & have a telescope of suitable aperture they are well worth the investment. The question is does a really expensive version make any further difference?

I have used a SkyWatcher Oiii for a number of years but have just pressed the button on an Astronomik Oiii, so I will be able to find out for myself shortly

I have been happy with the views through the SkyWatcher Oiii but I have tended to prefer the view through my UHC, which is from Astronomik. I haven't had the opportunity to compare like-for-like before, so I don't know if I prefer UHC to Oiii, or Astronomik to SkyWatcher. Watch this space...

[AndyWB]

FWIW, I've seen the Veil without filters, under beautiful dark skies, in a 130mm scope. I then added a Baader UHC-s filter - and it didn't really make much difference, to be honest. It was fantastic either way!

A couple of days after that, from a much more light polluted location, I tried again, with the same scope - and I couldn't even see the Veil. I added the UHC-s filter again - and I could see traces of it, albeit dimmer and less obvious, with much less detail. For a 'gentle' filter, it was a remarkable difference.

I guess my point is maybe that how effective a filter is depends on what you're trying to exclude, and under excellent conditions maybe they make less of a difference?

I am keen to try something more aggressive in the 10", though.

[RikM]

I didn't get any clear sky time yesterday but just looking through each filter in the daylight it is clear that the colour seems subtly different. The SkyWatcher is a more blue/green, where the Astronomik is green/green. If this translates in narrower bandpass or not, I don't know but they are definitely not quite the same shade.

[RikM]

I had a 2 hour observing session last night and spent most of it on filter comparisons. I will post a proper review when I have more time but in short, yes the premium filter makes a difference but not in the way I expected. The Astronomik OIII seems to have significantly higher transmission than the SkyWatcher. The SkyWatcher OIII gives more contrast but dims the view more overall and doesn't seem to add any fine detail to the view. e.g. on the veil, without a filter it was almost invisible. With the SkyWatcher OIII, there was a clear curving band of nebulosity with varying width but no real structure. With the Astronomik OIII, the view was brighter and there was less feeling of contrast overall but I could still clearly see the curving shape and now also filaments of brighter and darker structure within the band. Easily the best close up view of this object I have ever had. I used a 28mm/68º ES in my 10" Dob.

As I said, I will write up a proper review after a couple more observing sessions but from a first look, yes the premium filter is better but it's a different view rather than 'the same but better'. Is it £100 better??? I don't know... but I've spent it now so it doesn't really matter does it?