UHC or Oiii filters?

[Woking]

Hi

Any thoughts on which to get for visual use with the 120ED?

UHC filters are apparently better on a larger number of DSOs, but I've seen the Veil through an Oiii so just don't know!!!

Been looking at the Baader versions of both and they seem the best value for money....

I also regularly observe at a site affected by London LP in the east and am guessing the Oiii would be more aggressive and help more.

[JamesM]

I have no experience of using your scope but if you have a little bit of spare time, you might want to read this comparison review. In addition you might also want to read this general view of filters here.

James

[rory]

I have no experience of using your scope but if you have a little bit of spare time, you might want to read this comparison review. In addition you might also want to read this general view of filters here.

James

thanks for the link on camparisons, ive saved that for a read later.

early indications look like the uhc is best all rounder .

[cotterless45]

Yep,always had great results just with a relatively cheap SW UHC filter.

Nick.

[John]

UHC's are generally more versatile than O-III's, especially in smaller aperture scopes. I've found the Skywatcher, TS (Telescope Services) and Orion Ultrablock (a type of UHC) filters work well. The Baader UHC-S is good for small aperture scopes (less than 4" perhaps).

That said, I find the only filter I use now with my 4" - 10" scopes (including an ED120) is a 2" Astronomik O-III. I've had some fine sights through it and it seems to be of higher optical quality (ie: stars appear more sharply defined) than others I've used.

[RikM]

I have the Astronomic UHC and, for the winter objects where it makes a difference, I am glad to have it in my EP case. I've not had it long enough to try it on all the main summer nebulae, but it helps a bit with the ring. It is strange, but it seems the worse the sky, the more impressive is the effect of the filter.

Edit: I've just ordered a SkyWatcher Oiii from FLO as it has a wider bandpass than the Baader and I generally prefer a brighter image. Will let you know how it works in a few days

[rwilkey]

The SW UHC and OIII are spot on, I chose them because of the slightly broader bandpass and have not regretted it.

[Andrew*]

Skywatcher, Castell and Orion Ultrablock (UHC) are all good value filters. I have a Skywatcher OIII and an Orion Ultrablock. However, they are in the budget range, and you may be able to spot improvements in sharpness and maybe even transmission from the likes of Lumicon and Astronomik.

I would avoid Baader to be honest. Baader do not have a genuine UHC, and their OIII filters have quite narrow bandpasses, making them darker than others.

If you can only get one, get a UHC, but I would always buy both filters from the cheaper range rather than one premium.

[Woking]

Thanks everyone, some really good advice.

I did have a read of the useful Cloudy Nights filter comparison report before posting this thread, but was really after some good old subjective opinion based upon similar scopes.

Think I'll go with the Oiii but raising the budget to the Astronomik - John, your advice from the perspective of having an 120ED is really helpful (not the first time). Also, it's just that view of the Veil I had through the Nagler and Oiii, so the thought of a slightly diminished view by going for the UHC despite it's versatility could disappoint;)