Filters, what to get?

[Jules76 (Julian)]

Hi. I'm new to astronomy, hence why I'm here. I brought a Skywatcher SW450 114mm reflector about a month ago to start me off, and I'm been having fun learning the ropes and getting use to it all.

Anyway to my question. I do most of my star gazing in the suburbs, and while it's not too bad at times (I live about 30km's SW of the Brisbane CBD), there is still quite a bit of sky pollution as to be expected. Which got me thinking about filters for my eyepiece.

Now I'm under no preconception that that filters will be a solve it all solution, I know the best viewing conditions are for starters away from major population areas. But I just want to try and make the best of my situation which got me looking at Light Pollution Filter's.

First question I want to know, how much of a difference do they make?

Second question, what is the difference between the types you can get and which is better?

From what research I've done I've found 3 different types.

UHC-S Nebula Filter
Oxygen III Filter
UHC/LPR Filter

From the limited information I've found, they all seem to do the roughly the same thing except the UHC/LPR appears to do the most plus it's the more expensive of the 3 (which usually means it's better?). I'm confused as to which to get, if any.

Would really appreciate it if someone could shed some more light on this. Thanks.

[Kevnool (Kev)]

I reckon take the OIII off your list as your aperture of 114mm is to small and you wont see much at all through it.

Let others tell you about sky glow filters as i dont keep them ones.

Cheers Kev

[pgc hunter]

A UHC should work well with a 4.5" reflector. I've got a 4.5 incher and have enjoyed my UHC with it. It'll dim the stars, but nebulae will stand out with more contrast.

[Robh (Rob)]

Julian,
I have an Orion Skyglow Broadband Filter. It blocks the most common light pollution (e.g. street lights) but allows Hydrogen Alpha & Beta and double ionized Oxygen (OIII). I find the filter improves contrast between the sky and the object by darkening the background. Works well on bright nebulae like the Orion Nebula, Lagoon, eta Carinae Nebula, Tarantula, Dumbbell.
It won't make the object brighter. So it is not much use for dim objects e.g. most galaxies.

Regards, Rob.

[Jules76 (Julian)]

Thanks for the replies.

How would one of these filters affect viewing of planets? I'm not too concerned about reducing the brightness of stars, I'm more interested in viewing neblua's and planets if possible.

I was just looking at the Astronomik UHC-E which from what I've been reading is one of the best quality to get and is good for smaller telescopes like mine. Anyone had any experience with them?

Much appreciated.

[pgc hunter]

UHC and other nebula filters don't work on planets. These are strictly for nebulae only.

For planets you can get colour filters to enhance individual features such as jupiter's clouds, the martian polar caps etc, but the enhancement is very subtle, it'll tint the image and for a 114mm scope, many deeper colours such as red, violet and blue will darken the image too much. I have some colour filters but rarely use them as I just prefer the natural view.

[troypiggo (Troy)]

Planets are pretty bright and wouldn't need filters typically, would they?