Baader oIII & UHC-S filters

[Guest]

I am a kean visual observing star gazer. Looking forward to my incoming Celestron C9.25.I have always thought about the benefit of filters to enhance the views through the eyepiece.I decided on the C9.25 as it can easily be transported to darker sky sites.I suffer with light polution.What are the pros and cons of the title filters? Would it be wise to have both in the armory. Or just one or the other?

Any advice would be welcome.

Thanks

Grumpy

[John]

Hi Grumpy,

The UHC-S is a UHC-type filter designed for smaller aperture scopes. I'd suggest that your 9.25 would benefit from a "full" UHC filter such as the Orion Ultrablock or Lumicon UHC. O-III filters generally compliment UHC's and the Baader O-III is an aggressive O-III, that is, it's band pass width is pretty narrow so while the nebula contrast is enhanced you loose quite a lot of the background stars.

For your scope I'd probably not pick either of those but instead go for something like an Orion Ultrablock and / or an Astronomik or Lumicon O-III.

For quite a few years I was happy with just an Astronomik O-III which seemed to do excellently on a range of nebulae in all my scopes from 4" to 12" in aperture.

The Baader filters are fine in terms of quality but I just didn't feel their characteristics were what I was looking for. I have owned both in the past.

[Guest]

Thanks for that input John.I will take it onboard as I begin to use the scope.Birthday coming up aswell.

Martin.

[swamp thing]

As I don't use a SCT it's kinda tough to recommend a filter for them. Knowing what exit pupils are used the most often is the key to filter success.

Mr Wilkinson is probably the guy to ask as he has huge experience with SCT's