Filter help

[gooseholla]

Hello guys and gals.

I have a set of colour filters and a moon filter, but I am looking to add some more specialised ones to the collection.

Now, I understand there are light pollution filters, that do obviously what the name suggests. They call these nebula filters also. However, are these similar in effect to say other Nebula filters - UHC, OIII etc.?

Haven't got a lot of money to spend, but what do people suggest I should get for trying to find DSO and generally cut out the orangey glow of street lights?

Thanks

[rwilkey]

Light pollution filters do cut out the orangy glow from street lights and if you get the right LP filter it will help with nebula as well, as far as I know, only the Orion SkyGlow filter deals with LP, as well as let through the doubly ionized oxygen, Hb and Ha wavebands, however they are a little expensive, as are all 'nebula' filters. Failing this if you only want to buy one filter then I would recommend the UHC filter which greatly helps in the contrast of nebulae and filters out some orange glow, and gives a nice dark sky background. Against some nebula such as M42 it gives a rather attractive blue glow, whereas the OIII (which I love) is at the green end of the spectrum. It all depends what you want to see and hope to get out of it really. I only found my way around by experimenting, so be careful if you have not got too great an outlay, can you borrow any from friends or from an astro club? Many people have LP filters rather than any other I have found, even use them on the Moon (I don't). The Baader Neodynium filter has many supporters on this lounge, personally I have found it unspectacular IMO.

[gooseholla]

Thanks for the help.

I don't have any astronomy friends and my "local" club is too far away, as far as I know.

[rwilkey]

Hi gooseholla, that's a shame, that's a good way to try out things. LP filters quite often appear in ebay, that's where I got my SkyGlow. The Sky Watcher 1.25" LP filter is quite reasonable at FLO, this was the first one I bought: First Light Optics - Skywatcher Light Pollution Filter

[gooseholla]

Thank you. I've been looking at that Skywatcher filter for some time now.

[LukeSkywatcher]

The SWLPF does a good job of getting rid of the horrible orange glow.

[James4]

hi there Gooseholla, just to throw in my 2 cents worth, I was recently amazed by the effect of both an Orion UHC filter, and a Lumicon (pricey I know) OIII filter.

both of them literalley made the invisible, visible!

I was using a short f6.5 6" achro refractor. The objects were: The Veil, The Helix, and The N.America Nebula. Without the filter I could see nothing. Now I can't decide which one I need most.

[rwilkey]

That's easy, they are both useful and great quality, keep both!

[great_bear]

Thank you. I've been looking at that Skywatcher filter for some time now.

Bear in mind that both the Sky-Watcher Light Pollution Filter and the Baader Moon & Skyglow filter only filter "traditional" street lights.

If you live in a modern city you might find - as I did - that the light pollution filters simply don't work. Literally no increase in contrast whatsoever. It depends on the local conditions where you live.

Narrowband (UHC / OIII filters) on the other hand, pass such a small band of light that they have an effect under all circumstances. However, these filters only work on specific objects, and if your sky is swamped with light pollution, even these won't help.

[rwilkey]

Great_bear, I agree entirely with your sentiments, what you say is very true, however, the SW Light Pollution filter is a very rasonable price at FLO and would be good to try out first, if you are not sure. As mentioned earlier, I have tried a few and they work in my area, but I only found this by trying them, the SW being the first, dead pleased.

[tombulgin]

I asked a similar question a few days ago on here and got some great replies (search on my threads in beginners section). i was more interested in UHC or OIII. one of the responders,(apologies, names escapes me), posted this link - very interesting reading and reference: Filter Performance Comparisons - Article

I have gone and broken the bank and ordered an Astronomik UHC filter. hoping it will be here for moonless skies in run up to Xmas!