What Filters?

[Les S]

Well its birthday time at the beginning of September and the family have decided to pool their resources and buy me items for my new hobby.

First on my list are a couple of new EPs from the BST range.  I do have some light pollution in the garden and was wondering if a filter would really be of help.

I have read all sorts of reviews but thought I would ask for some advice from those with the experience.

Is there a filter to see through the clouds.  (if only)

Many thanks

Les

[laudropb]

It really depends on the type of LP you suffer. If it is from Orange sodium street lamps then a light pollution filter usually does help. If it is from security lamps or most types of white light it will probably make little difference.

[ronin]

LP filter will depend heavily on the nature of the LP.

They were initially for sodium lights, then they had high pressure sodium that were not quite as yellow (still a good bit), then we have the white industrial types and now the LED's.

I think only the old simple sodium lights were really countered by a light pollution filter, nice narrow bit of the spectrum to block.

They have improved the IDAS P2 are good but still white light causes problems. However the IDAS are fairly costly and if no use then you are not going to be happy.

Difficult to say go buy XYZ, as there is no XYZ that does it all.

You might be better with an OIII filter or the UHC ones for nebula - depends on the nature of the emission. So again does not cover everything, will however block some of the light pollution, as they pass a narrowish set of wavelengths.

I have managed to get by with none.

Maybe one day I will try, but caught with the "problem" that observing away from home tends to have some light pollution (white) and although my street lights go out at midnight and it is dark, owing to a house (mine) and a few trees (mine again) the view is limited.

Which BST's are you thinking of?

[Les S]

The lights causing the polution are sodium. There are two which are on a foot path about 30 m from the back of my house.

Re the EP'S I am thinking og 8mm and 18mm.

Les

[RT65CB-SWL]

The lights causing the polution are sodium. There are two which are on a foot path about 30 m from the back of my house.

Re the EP'S I am thinking og 8mm and 18mm.

Les

Hi Les, I find the Baader Neodymium filter works.

 

I read somewhere that Wokingham DC in the process of changing all street lights from Sodium to LED's over the next few years. Where I am, I have a mix of Sodium & LED's, plus the lighting from the leisure centre and supermarket.    

 

[spike95609]

It might be just me and my limited experience but I've not found filters to make much difference at all. I've got a Baader Neodymium amongst them, and have sodium lighting around me, but if it does make a difference it's very subtle to my eyes.

[John]

It might be just me and my limited experience but I've not found filters to make much difference at all. I've got a Baader Neodymium amongst them, and have sodium lighting around me, but if it does make a difference it's very subtle to my eyes.

Thats what I've found as well over quite a few years of trying !

What I use now for nebulae are UHC and O-III type filters and those do help to bring the nebulosity out, in some cases substantially, despite some light pollution issues that I have. For other DSO types (eg: galaxies and fainter clusters) I time my viewing to coincide with them being as well placed as possible, ie: well above the horizon and in parts of the sky least affected by LP, trees, neighbours houses. This seems to be the nature of backyard deep sky astronomy !

So I'd recommend a UHC or an O-III filter for nebulae but for galaxies and other DSO's session planning and nimblefootedness help a lot !

[spike95609]

Ah now I do have an OIII in my little collection and that's the one which truly makes a big difference on certain nebulae. e.g. on the Veil - I saw a fair amount of faint structure with an OIII, but without a filter it simply isn't there at all. I might consider adding a UHC eventually. So yes I can see the benefit in nebula filters, but am unconvinced by ones which say they'll help with light pollution.

[Charic]

Forget the filters, from the advice above. I too own a filter, no change visually?

You can extend the telescopes length by adding a circular tube of camping carpet underlay foam. That helps, better and cheaper  than a filter.

Your choice of the BST 8mm and 18mm is spot on. The rest will follow, they are a fantastic basic upgrade for their outlay. I also wanted to invest in a Plossl type eyepiece set.  I found Astroboot have some GSO/Revelation Plossl's for about £15. Their very good, but wont have the same eye relief or field of view that the Starguider ED's offer?

I'd ask the family if they can buy you a Cheshire tool from the same place you buy the BST's Buy the Long version Cheshire tool. You`ll need this when tuning the telescope ( collimating) from time to time.

You have a great scope. Any of the EPs in my signature work well. A 6mm will get you the 200X magnification that the scope is capable of producing. BST Starguider 6mm not available yet?

Enjoy your new telescope.

[Les S]

Thanks Charic,  I already have the Cheshire but so far have not had to use it.

[Charic]

Thats a good sign. If handled carefully the Skyliner holds collimation well.

 The 12mm  BST ED Starguider is also a nice eyepiece on the Skyliner, this can be Barlowed  well to give you the 200x power.

The 8mm 12mm & 18mm Barlowed gives you as good a range as any  ie ( 4, 6, 8, 9, 12, 18 )  300x down to 66x. If you find a 32mm Panaview,  going cheap, then your set.

There are other premium eyepieces out there, some probably finer, but not  in the same  price range.  Look around, I've seen a couple recently second hand? 

[Les S]

Thanks everyone for the advice

Les