Light Polution Filter v UHC OIII

[dcwales2012]

Hi,

Advice sought on filters please.

Which would be better of the two for seeing?

What is rule of thumb on quantity? I would imagine they are fiddly to swap between EPs in the dark!

I was considering getting one of each time; Baader, and putting the UHC on 32mm for Nebula seeing, and the Neo on 5mm for planetary seeing.

But I would be grateful for advice from others.

Location, semi rural with the odd white street light, no orange sky glare, however in far distance to south have glare caused by open cast coal mining activities, which does effect seeing when aligned in that direction.

Normally out on Brecon Beacons as couple of miles away, so filter only required when I'm viewing from garden.

Regards

David

[bingevader]

There are a couple of good threads on this subject already if you have a little search around, especially in the eyepiece section.

It depends on what you are wanting to look at and the conditions at your site.

The different filters filter out different wavelengths of light in order to see objects that emit various wavelengths more clearly.

These tend to be used most on diffuse emission nebulae and planetary nebulae.

If you just want a light pollution filter, then almost any of the broad band filters such as the UHC-S would be fine.

Don't rule out the use of filters in the Beacons though, as they can enhance some of the more difficult DSOs already mentioned.

Then you are into specifics depending on what type of nebulae you want to look at.

This thread has a couple of links that go into it in much more detail.

Cheers

[todd8137]

Hi. From me its horses for course what scope do you have ?,i was once in your position this one or that one in the end i got the lot. A neo ,uhc, lightpollution oiii

if its a small scope some of these filters will be good for nohing others will be great

what scope do you have

pat

[dcwales2012]

Hi,

Trust me to miss out the important info: SW 150p (f5) on EQ5.

David

[rwilkey]

Hi David, to be honest, I think most of us try the lot, I certainly have but would advise against a light pollution filter, as all the others do the same job by concentrating only on certain wavelengths. I sold my LPR filter recently as I no longer used it. In order of usefulness I would go for the UHC followed by the OIII. The Baader Neodynium is a luxury item in my view but a good filter, helpful with some planets and moonglow. Another thing, it's better to buy 2" filters in my opinion, these can be screwed into the 2"-1.25" adaptor when using 1.25" ep's, then you will have a filter for both ep barrel sizes, just saying this as it might save you money later, though too late for me haha!

[dcwales2012]

Many thanks for replies.

Sound advice Robin, never gave 2" a thought. Never too late to learn, or to spend the wifes money on something useful.

David

[LeeB]

if you use the 1.25 filters, I pop a short extension in made from a cheap barlow with the barlow bit unscrewed,that way you can leave leave the filter in situ.

[LukeSkywatcher]

UHC and Oiii filters are both useful.............but for different objects. A UHC filter is more widely used to enhance the views of already visible to the naked eye nebulae while Oiii filters bring out nebulae that are almost of completely invisible to the naked eye. Both work as light pollution filters in this regard because they only let certain light pass through while blocking the rest. However...................both will block out most light from stars and the image will be darkened as to enhance the nebulae you are observing, so i think its still a good idea to have a standard light pollution filter for those times when you are not observing nebs. I have one of each: LPF,UHC and Oiii and they all work well for me from my back garden. I'm about 20Km south east of Dublin city on the coast. Its not very heavily light polluted.............but its bad enough to need these filters. All of mine are the Skywatcher brand.

As Robin said: UHC first,then Oiii. I wouldnt leave out a standard light pollution filter though.....................in saying that...................you may not need one as you are semi-rural and it depends on what type of streetlights you have around you. If they glow orange then you might need a LPF. If they glow white you might be ok.