Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

O-III FILTER?

starstalker

Recommended Posts

  • Replies 32
  • Created
  • Last Reply
great_bear

great_bear

Posted
Posted

If it's just for visual use, the Orion Ultrablock works for me, although the Sky-Watcher OIII is cheaper.

Note that the Ultrablock allows Hydrogen Beta through as well as just OIII.

Don't buy the Ultrablock from Telescope House though, as they seem to have an error (I assume) in their price list, which mistakenly puts the 1.25" Ultrablock at about £120 when it should be more like £70.

Link to comment
Share on other sites
Chris H

Chris H

Posted
Posted

In Sky at night magazine last year they reviewed filters and the Orion Ultrablock came out top (I'm often slightly dubious of these reviews but have read elsewhere that these filters are good). It beat the Lumicon into second place and is a lot cheaper. Jahmanson on the forum rates his Astronomik OIII filter and you can see a sketch DOC made here http://stargazerslounge.com/imaging-sketches-unconventional/113910-kelling-sketches-veil-nebula.html using his Baader OIII filter (but also a 16" scope)

If it were me and money no object I would go for the Lumicon they seem to be the industry standard.

Link to comment
Share on other sites
John

John

Posted
Posted

I've owned a Baader OIII, a number of UHC's including an Orion Ultrablock and my current Astronomik OIII.

All were pretty effective but had different characteristics of course. Persoanlly I found the narrow band pass width of the Baader a little too "aggressive" and only of use in medium or larger aperture scopes. I liked the Ultrablock a lot but the Astronomik is the best I've tried so far - it's really somewhere between an OIII and a UHC and therefore very versatile, even in my 4" scope. It also uses high quality optical glass which delivers much sharper star images than other filters I've tried. Like most quality items you do pay for this of course - the Astronomik OIII, in the 2" fitting that I use, costs £172 new - luckily I found mine used at much less than that - otherwise I'd still be using the Ultrablock !.

Often folks seem to have both UHC and OIII filters but I find the Astronomik a pretty good "1 filter solution".

Link to comment
Share on other sites
LukeSkywatcher

LukeSkywatcher

Posted
Posted

If the SW O-III filter works anywhere near as well as the SW LPF then i'd think it is worth a shot at. Having said that, the Castell also seems like a very good option. Now the silly season is nearly upon us i must get myself one of either. I remember reading up on the Castell at the beginning of the summer and promised myself i'd get one soon. Might be time.

Link to comment
Share on other sites
John

John

Posted
Posted
How does that work? An O-III transmits O-III and a UHC transmits O-III and H-beta -- i.e. where is the "between"?

I believe that the Astronomik OIII transmits a little H-beta as well as O-III. I don't care too much TBH - I just know that it's a great filter to use and I prefer the views it gives to all the others I've tried :)

Link to comment
Share on other sites
BinocularSky

BinocularSky

Posted
Posted

Very informative graphic; thank you. However, looking at Christian Buil's filter transmission curves , and taking the 90% pass as a comparison, we seem to get the following (approximate):

Lumicon OIII 490-505 nm

Lumicon UHC 470-505 nm

Astronomik OIII 495-510 nm

Sorry to be a pain....

Link to comment
Share on other sites
LukeSkywatcher

LukeSkywatcher

Posted
Posted
I don't know enough about them to be honest to answer your question :)

Like John I see what I like and I like what I see but don't really understand why (me at least the last bit).

I agree. I am purely an observational type. I dont really care about the science or maths behind the gear i use or the science maths of anything in the universe really. If i like what i can see that is all that matters to me.

I cant honestly tell the difference between an arc second and Noah's arc. Nor do i care to know.

Astronomy for me is about relaxing and enjoying the views. If i had to calculate everything and work out angles etc.................i would be gone from the hobby even before i started.

Link to comment
Share on other sites
glowjet

glowjet

Posted
Posted

I don`t think we ever stop learning, Astronomy is such a vast and diverse subject, I was under the impression that O-111 filters are not really any good in small scopes, I was therefore quite surprised to learn that the authors of "Illustrated Guide to Astronomical Wonders" had used one to great success to see the North American Nebula, in nothing more than an 80mm short-tube refractor, without it nothing could be seen at all, the book by the way is one of the best for finding and locating DSO, a bit like TL@O but more in depth with maps finder circles and photos for each subject, all 110 Messier and a wealth of NGC and others besides.

John.

Link to comment
Share on other sites
John

John

Posted
Posted
I don`t think we ever stop learning, Astronomy is such a vast and diverse subject, I was under the impression that O-111 filters are not really any good in small scopes, I was therefore quite surprised to learn that the authors of "Illustrated Guide to Astronomical Wonders" had used one to great success to see the North American Nebula, in nothing more than an 80mm short-tube refractor, without it nothing could be seen at all, the book by the way is one of the best for finding and locating DSO, a bit like TL@O but more in depth with maps finder circles and photos for each subject, all 110 Messier and a wealth of NGC and others besides.

John.

As has been implied by the responses in this thread, not all O-III filters are the same. Some (like the Baader) have a narrower band pass width which makes them less satisfactory to use with smaller aperture scopes. I happilly use my Astronomik O-III with my 4" refractor and it shows a great view of objects like the Veil Nebula complex on dark nights, objects that a virtually invisible in that scope without the filter.

It's true though, we are learning all the time :)

Link to comment
Share on other sites
MikeWilson

MikeWilson

Posted
Posted
I know that to be plain wrong; I have used a Lumicon OIII with a 6mm "scope" at x1 (aka the Mk-1 eyeball) -- you wanna see the veil naked eye? :)

Seriously? Wow.

I was considering getting the Skywatcher UHC filter which lets through a little more than OIII, but now I think I'd like to try the OIII too!

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.