Do I need an Oiii filter?

[David Niven]

I was observing the Orion Nebula the other night and the sight was not as impressive as I would expect on my 10ins dob.
Should I use a broadband filter or an OIII filter?
Can these filters improve on the nebulosity?

[astroron]

Hi David, it all depends what you expect:shrug:
If you expect to see what you see in pictures here in iceinspace and elsewhere then you will be disappointed, the eye does not see the colours that you see in the pictures.
A 10" scope with a low to medium mag eyepiece will give you splendid views of the Orion Nebula.
There are a few things that can spoil you views, One is poor seeing ie, shimmering and fuzzy stars, light polution, and poor collimation.
A UHC filter will enhance your views of most Nebula and still give you some stars as well.
O111 filters are mainly good for Planetary Nebula , but they darken or even remove most of the stars.
There is one thing that will improve your observing and that is experience .
As you observe more you will begin to see more datail in objects like the Orion Nebula :)
Cheers :thumbsup:

[Saturnine]

G'day David

The use of filters will certainly help to increase the contrast between nebulae and the background sky. This is more evident if you are observing from light polluted suburban areas or in moonlite skies. If you are trying to observe nebulae without a filter from light polluted skies , all but the brightest knots will be washed out, the sollutions are to move to dark skies or wait till there isn't a bright phase of the moon, not always practicable or, to start with, invest in a broadband nebula filter, which will be more versatile than a narrowband filter such as an Oiii .
Can thoroughly recommend using a broadband filter for most nebs like M42, M8, M17, NGC 3372 The Carina Neb, etc etc. See if you can borrow one to try out and compare the difference in the views with and without the filter. Hope this helps.

Jeff

[Poita]

If you want to try out an OIII filter and a nebula filter, drop me a PM and I'll post you mine to try out.

[Forgey]

Just reading thought this thread and then did a google search and came across this article http://www.astrobuysell.com/paul/filters.htm
Might be useful to some.

[Davekyn]

WOW :eyepop: ... not used to seeing that, could I try something too please. :D

I think I will be leaving the OIII filter till I get some more experience. At the best of times it takes more than it gives ... perhaps knowing what targets are best used in it first and being well acquainted with all the right variables to be in a position to use it first will better serve you ... definitely for the experienced I would say.

The UHC on the other hand is a must IMO. The view in a 12" Dob blew me away the first time ... the UHC filter Blew me away a second time!

[Poita]

Sure, if you want to borrow any filters or eyepieces, then let me know.
I think the only way to know if you will get any benefit from these type of things is to try them out.