What does an OIII filter do?

[midge91]

I have been recommended an OIII filter but still not quite sure what it does. From what I can gather it gives the nebulae its colourful 'clouds'. Is this correct?

[NickK]

An OIII filter will only allow light at a wavelength of the emission spectra of oxygen-3. As some DSO targets have light emitted at these wavelengths, adding a filter allows you to block out the other light wavelengths.

[midge91]

An OIII filter will only allow light at a wavelength of the emission spectra of oxygen-3. As some DSO targets have light emitted at these wavelengths, adding a filter allows you to block out the other light wavelengths.

Might sound stupid but this does what exactly? Sorry Science is not my best subject and I'm a beginner to astro

[todd8137]

well in a word no,it will bring more of the cloud out in the great Orion neb and give it a green tinge the back ground will be more darker the stars will go greenish ,but the neb will have more detail,you will see more of it and there is more fainter clouds that appear with the filter,them m57 is another good one this pops out for me dumbell broom handle ect i never could see m1 till i got this filter its very aggressive i also have a uhc s filter which is not bad but a better all rounder for me but the 0III filter is good i like it

[foundaplanet]

Might sound stupid but this does what exactly? Sorry Science is not my best subject and I'm a beginner to astro

Try this it should help explain

Edit: Sorry I posted you the wrong link... Try this one http://karmalimbo.com/aro/filters/article_Astronomical%20Filters_Part%203%20Deep-Sky%20Filters.pdf

[ChrisThePuma]

Hi

my understanding (still a noob) is that it will give you better contrast and thus you will see more of the nebular cloud (but still in black & white - you will only see colours in photos)

personally i am going to get a UHC filter as they seem a bit more versatile than the OIII one.

check this link for more info:

http://stargazerslounge.com/primers-tutorials/84192-primer-understanding-choosing-filters-visual-use.html

[GazK]

If you want a single simple reason why you should own this filter: look up "veil nebula monochrome" on google images. Without an O-III, you can stare and stare at this object and all you will see is a star field. With the O-III, you can see it stretching from one edge of your wide angle eyepiece to the other. A real "wow" moment and IMHO worth the expense of this filter.

Of course you'll need to wait until later this year for this object to be at its best but that gives you more time to save your pennies!