Which filter?

[T A WOW]

Hello all.

I'm looking at buying a couple of filters for some visual work. Firstly I want to get an achromat filter.

The two I'm looking at are both baader (love their stuff).

A fringe killer. http://www.firstlightoptics.com/achromat-semi-apo-filters/baader-fringe-killer-filter.html

Or a semi apo. http://www.firstlightoptics.com/achromat-semi-apo-filters/baader-semi-apo-filter.html

Any one know what the difference is between these two other than £10?

Secondly I want a filter for looking at nebulae (spelling?) don't know what type. I was looking at (again baader) filters such as an Olll or UHC but I remember borrowing a H-beta filter or Ryall (I think) and I can't seem to find these anywhere accept in CCD filter sections.

Do you get different H-alpha/beta Olll Slll filters for visual and CCD or can you use them for either?

Thanks.

[oldfruit]

Hi Tobias, I have used a fringe killer and owned a semi apo filter. I take it you would be using it in you 6 inch refractor? I also used mine in a 6 inch refractor. I personally found the Baader semi apo filter the better of the 2 as I leaves the image with a more natural colour. The fringe killer had more of a yellow cast to the image.

 

http://stargazerslounge.com/topic/30187-baader-ca-filter-comparison/ Here is a useful comparison.

 

Hope that this helps?

With regard to Nebula filters, O111 filters and UHC filters are good for visual and work very well on a large variety of nebula, the H-beta is very limited as it is only useful on a few objects I believe. I am sure that someone else may be able to explain better and in more detail.

[philjay]

Yep the fringe killers give a yellow tint but if you can see past that they work ok.

An o3 is a must for planetary nebula. I also use a h beta filter for emmission nebula, gives a new dimension to them, i use it quite alot.

Uhc are good for enhancing nebula.

[T A WOW]

Most useful yes thank you. I'll be getting the semi apo one then.

Obviously I would be using that one in the F8 frac

The others I'd more likely use them in my 10 inch newt (maybe)

[+Ibbo]

I like the UHC-S filter with the dob

also the O3

 

but if I was going for 1 of them UHC-S would be the one

[oldfruit]

I like the UHC-S filter with the dob

also the O3

 

but if I was going for 1 of them UHC-S would be the one

Personally for me is a little different, (not that I want to argue with the more experienced observers) whilst the UHC-S is a good filter (I had one before) there are a lot of objects that actually show better in the O111 filter? In my (limited) experience the O111 filter gives better contrast over the UHC-S filter, Not always but in most cases. I have recently purchased the Skywatcher 2 inch O111 filter and it is great. My initial impressions of this filter are very good.

[T A WOW]

What filter would make M42 have more detail in it? The Olll or UHC?

[xanthic]

This is a fairlt comprehensive review of filters and their effects on viewing DSO -

http://www.prairieastronomyclub.org/resources/by-dave-knisely/filter-performance-comparisons-for-some-common-nebulae/

Edited September 29, 2013 by xanthic

[philjay]

Uhc will help with m42. H beta also brings out lots of extra stuff as well i find, gives it a real boost

[Guest devil74]

Morning boys

Can I just add to this discussion because I'd like to know what sort of mag you might use for looking at nebulae? Not tried it yet but definitely will be over the next few months as I build up more equip.

Also I'm building up the range of Vixen LVW's which would force me down the 1.25 filter size..now after Kelling I'm thinking of getting an ES 30mm so would I be better getting 2" filters for this EP?

Damian

[BAZ]

It depends on the type of nebula you are after. Typically Planetary nebula are small and difficult to find, M57 needs at least 100x to get a decent view of it.

Others such as reflection and emission nebula can be vast, and you won't even get it all in the scope. M42, the Veil and North American nebula are good examples.

 

My favourite eyepiece for this is a 2" one, 26-35mm would do well, and the 30mm ES should blow your socks off.

[T A WOW]

Well. After opening my post this morning and finding a cheque off n power for £243 I may just treat myself to the Olll and UHC. Happy days!

[BAZ]

Happy Day's Tobias! 

[+Ibbo]

that has solved that problem then :D

[catman161]

Sweet! Happy days indeed

[Doc]

If you want to know what objects are best viewed with what filter, check this out.

 

http://www.prairieastronomyclub.org/resources/by-dave-knisely/filter-performance-comparisons-for-some-common-nebulae/

[Werisit]

Tobias.

Just ordered a Baader Fringe killer to go on my SW st 102 achro. On the basis that it has minimum light loss and with only 102 aperture I need to keep as much as I can. I experimented on the moon with a yellow filter and found it improved the sharpness noticeably. And it was worth the colour cast to get the improvement. 

I'll post again on what I think of it after some testing.

[Werisit]

Hi Tobias.

I'd be interested if you would post your opinions of the filters you've bought on various objects when you have had a chance to evaluate them.

I'm still waiting for some decent clear skies to have a proper go with the fringe killer!