Light polution

[Squif]

Hello!

I was wondering whether anyone uses light polution filters and are they really worth it?

I live in a city (not an awful lot of light pollution if you look in the right direction but enough to take the endge of things)

Also which filters would you recommend? is there much difference between the Baader Neodymium filter or the skywatchers LP filter?

[rjsc2001]

I'm considering the Baader Neodymium filter just by the specs. I never saw through one.

I do believe they are worth it, but not the extra expensive ones.

ricardo

[Stephen]

There's virtually no difference between the two (There's a comparison somewhere on here that I can't find at the moment.)

They work well, with the right sort of LP. The same filter can do wonders for some, but have no visible effect for others.

I "think" FLO will accept a return if you aren't happy with the filter. Might be worth giving them a call and having a chat about it

[Squif]

I think I will give them a call- from what I have found aparently the build quality of the baader filter is alot better then the skywatcher one. Think I will ask FLO and see what they say.... will post back!

[RikM]

I use a SW LP filter which is very similar to the Baader Neodymium. For imaging it really does make a dramatic improvement, but for visual use it doesn't do a great deal and so I generally don't bother.

I am considering an Oiii filter for visual use instead but they dim the view quite a bit so you need a reasonable apperture scope with these type of filters.

[umadog]

Light pollution filters make a vast difference for visual observation of emission nebulae. There are plenty of emission nebulae to observe. Just the other night I saw 4 or 5 faint ones from mag 5 skies that were visible with a filter and invisible without. Really worthwhile.

LP filters will be of little help with galaxies or reflection nebulae. These sources emit broad-band light which can't be isolated effectively from light pollution. Emission nebulae emit in discrete bands (for the most part) and so these can be isolated.

Note of caution: not all filters are made equal. The characteristics of different manufacturers, say, "UHC" filter does vary. Some are better than others. Don't just buy the cheapest.

There are good reviews on Cloudy Nights along with very detailed logs of what the filters work on. These have been conducted by David Knisley. If for some reason you need to join CN to view the links, then do so. It's free and the information is beyond useful. The links are:

CN Report: The DGM Optics NPB Nebula Filter - CN Report

Filter Performance Comparisons - Article

Useful Filters for Viewing Deep-Sky Objects - Review

CN Report: DGM Optics GCE Filter - CN Report

CN Report: DGM Optics OIII Filter - CN Report

Orion SKYGLOW Broad-band Light Pollution Filter - CN Report

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/4754558/Main/4753400

Final note. Basically there are three filter classes. The broad-band light pollution filters (sometimes called "sky-glow" filters). The narrow-band ones (like the UHC). Then the "line filters" such as OIII and H-beta. Experience indicates that the UHC filters are the most useful, followed by OIII. Until recently, it was considered that H-beta was only useful on two or three objects. David's careful work has shown this to be false: this filter is useful on a selection of objects, although less useful than the other two. Standard advice is to go for the UHC filter first, then the OIII if needed. You'll get the most contrast boost per groat this way.

For UHC, the Lumicon of DGM are very well thought of. DGM may even have the edge and it's cheaper. For OIII, the Televue and Lumicon are often recommended. I've heard the Celestron OIII is good, but I've not tried it. From personal experience, I can tell you that these filters will work very well with 8" or 10" scopes and up. I haven't tried smaller apertures, but they should also work if you keep the power low. You need to be well dark adapted, though. You also have to use lower powers than you'd normally use. If you don't abide by those rules then you'll be disappointed.

[Stephen]

Here's the comparison I couldn't find yesterday

http://stargazerslounge.com/equipment-reviews/71126-skywatcher-lpr-filter-vs-baader-neodymium-filter.html

[Squif]

****** - now i am more confuddled --- to many decisions! although im not 1000% sure that I need one hahahahahahaha. time to do more research me thinks!

Thanks for your help!