Nebula filters, how much do they work?

[Manok101]

How much of a difference when looking at nebula will these filters make? Will it be night and day? or will it still be pretty hard to locate nebula?

[Rui]

First thing to keep in mind is: a nebula filter won't make nebulae brighter. In fact, as you're looking through another piece of glass, it will in fact block some brightness of the object.

However, it will increase the contrast between the nebula and the surrounding sky. This will eventually enable you to see a nebula that otherwise would be lost in the light-polluted background sky.

With a small telescope, like a 60 ou 80 mm refractor, the loss of light will not compensate the gain in contrast, but in an 8" scope you'll certainly see a remarkable difference. I have the Orion Ultrablock and it really works.

[John]

I've tried a number of these filters and found the narrowband type (ie: UHC, Ultrablock and O-III) ones effective on enhancing the contrast of nebulae. They do not have any benefit on galaxies - no filter does as far as I know. The impact is subtle on some objects and more pronounced on others. Planetary nebulae (eg: the Ring, the Dumbell, the Owl) and supernovae remnants (eg: the Veil) are the most improved. On nebulae such as M42 in Orion there is an effect but, personally, I prefer the un-filtered view.

I have an excellent 0-III filter (Astronomik) but I don't use it that much to be honest as most of my observing seems to be of objects that don't benefit from it. For certain objects through it's indespensible.

The Orion Ultrablock mentioned by Rui is a pretty good filter and costs less than the Astronomik. The Skywatcher and Castell UHC's are also good and cost a bit less again.

These are good "tools" to have in your kitbag for the right occasion but they won't revolutionise your viewing.

[bish]

I've used an Antare LPR on my 6" and 8" scopes and found it very useful to help pick certain DSO's out. Not a 'night and day' difference, although it did help me see the Veil when I kept missing it without.

[NGC 1502]

Agree with above posts. I've got Lumicon UHC & OIII. I wouldn't be without

them, although I don't think they should be the first accessories to get. Good

eyepieces should come first as they will be used on all objects, filters are only

useful for some specific objects.

If you do get a filter, a UHC is the most useful I think. The OIII is brilliant on

the Veil SNR.

Best regards, Ed.