wanted information on the best performing 2" minus violet filter/fringe killer

[h0ughy]

Ok I need some advice for the best fringe/minus violet filter?

can anyone help!? :help3:

[anthony2302749]

Hi

A while ago S&T ran an article on fringe/minus violet filters. The conclusion was the Baader Fringe Killer was better of the filters tested. Sorry I can not help you further I would need to go through all my copies of S&T.

Anthony

[h0ughy]

thanks Anthony

[jC_7]

Hey H0ughy,

I have the Baader Fringe Killer I use it on my 90mm F6.6 refractor.

I'd say (in my very newb opinion) that it works good, however, and it have read this elsewhere too, it puts a yellow tint on objects, most noticably the moon.

Now, I also have a Baader Moon and Skyglow filter, when I use both that and the Fringe Killer the yellow tint goes away as does the CA, albeit with a little less light transmission.

I find that I only use the Fringe Killer on really bright objects (venus, moon..) at magnifications of ~100x on my scope, and when I use the fring killer I typically end up always using the Moon and Skyglow filter in conjunction with it as well, but since the objects are bright the reduced tranmittence is not a problem.

So I guess the moral of the story:
Bright object = CA
with Fringe Killer = Yucky yellow tint (IMO) but "no" CA
with Fringe Killer + Moon & Skyglow = Natural colouration and no CA.

I say "no" because one could argue that the yellow tint is a Chromatic Abberation... though not one caused by out of focus light.

Hope this helps !!

-Justin

[cventer]

What is your intended use ? Astrophotography or visual ?

[Robert_T]

Hi hougy, I use the WO minus violet filter that came with the Zenithstar 80 package. I also have the Baader IR/UV block filter. Both help wth violet fringing. The WO seems better at reducing that violet fringing on the moon and venus, but it does (as Justin mentions for the Baader fringe killer) seem to give a yellow tint but doesn't trouble me. The Baader fringe killer might be better if you want to do CCD imaging as it also kills the IR end of the spectrum.

cheers,

[h0ughy]

both I think, the scope i wish to get is that sexy looking orion express 80, and that is because of size and portability. i intend to have a small rack of glass bits ranging from a Intes M500 then the Orion Express 80 then my 50-500 sigma APO lens and camera. I figure I can use the m500 or the express 80 for autoguiding with the St4 depending on what I want to look at and also photograph throught both of them. All this on a EQ6 with synscan. I have a DSI and the LPI, so I can probably achieve anything I couldn't 6 months ago. Apart from looking awesome, i should be able to cover what I want to achieve for the moment. ;) :)

[h0ughy]

As I have 2" EP's I will need to get the 2" filter, and the cheapest option is the Baader one. I hope I can live with the colour, but then sometimes the CA does give some life to some photos for arts sake :lol: . Years ago, and I mean years, I had a Tasco 80mm refractor made in Japan. It had glass elements not coated, and .996 Ep's. bright objects did have CA no that i think about it, but it didn't bother me then. If I really want pinpoint shots I will use the M500 with a 6.3 reducer. Life is just an experiment anyway, so I will give it a go.

So what do you think of your WO Zenithstar (same as Orion Express)?