Best filter for imaging narrowband with the ASI 552MM Pro.

[wavydavy]

What do you consider the best filter for imaging narrowband mainly h-alpha, I currently am using a Baader 7nm 1.25"................is there anything better, make/quality etc. The camera is an ASI 553MM Pro.

[Elp]

Astrodon and Chroma. But you'd have to weigh up whether it's worth the substantial cost for "marginal" improvement, people tend to buy them as they mitigate halos around bright stars which the baaders (and other brands) are notorious for.

[geeklee]

48 minutes ago, wavydavy said:

Baader 7nm 1.25"................is there anything better,

As well as the more expensive brands you can also look at narrower band pass options (less than 7nm).  These should offer more contrast, subtle going from 7nm to something like 4nm but noticeable (to my eye anyway). 

Is there a particular issue you're having with the Baader 7nm?  I still have fond memories of that filter, even moving on since.

[wavydavy]

48 minutes ago, Elp said:

Astrodon and Chroma. But you'd have to weigh up whether it's worth the substantial cost for "marginal" improvement, people tend to buy them as they mitigate halos around bright stars which the baaders (and other brands) are notorious for.

Is this what the issue is with this pic??

[Elp]

There's a small amount on the one side of that brighter star on the RHS but usually its a uniform sized glow around the star, if you try imaging Vega/Alnitak etc you'll likely see it more pronounced. I think that image looks fine. I've got baaders and can't really justify needing any others, they're expensive enough as it is.

[The Lazy Astronomer]

A point to note is halos are not necessarily solely the fault of filter, but can be the result of interactions between flatteners/reducers, filters, and camera cover windows. But I'd say there's nothing wrong with that, those halos should be relatively easy to deal with in post processing.

[Adam J]

On 26/09/2023 at 17:34, Elp said:

There's a small amount on the one side of that brighter star on the RHS but usually its a uniform sized glow around the star, if you try imaging Vega/Alnitak etc you'll likely see it more pronounced. I think that image looks fine. I've got baaders and can't really justify needing any others, they're expensive enough as it is.

yeah that's not a filter halo that's from a curved surface or it would not be offset from the star like that. Filter halos are almost universally centred on the star as you say.