Narrowband filters and mid-summer twilight

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Hi All

The skies where I live are now lighter at night with the continuous twilight of mid-summer. At this point I normally give up on using the telescope until maybe mid August.

I am new to using filters and I am wondering whether NB filters might allow me to continue imaging through the summer twilight ? Is this a thing that people do or is it just a stupid idea ?

Thanks.    

[daemon]

In principle I don't think it's a bad idea. I have a set of NB filters and am eager to use them but would say there are two things from my POV to consider:-

1) Guiding - you probably want long exposures for the subs, to gather enough data and guiding is likely to be needed to allow this. 

2) Target Selection -  sadly this is the blocker for me. The only viable NB targets worth imaging that I am aware of in the Northern Hemisphere at this time of year lie in the East and mostly around Cygnus (Elephant's Trunk Nebula etc) and as I have trees to the East I can't effectively image that area for long.

So, if you can see decent targets from your location and you can run decent exposure lengths, then maybe it is a viable exercise. For me - unless anyone has another suggestion - I think I will be sticking to broadband galaxy targets until conditions and target locations permit.

Happy to be corrected though!

Good luck!

daemon Steve

[ebdons]

Yes you can do NB imaging, depends on object magnitude ,sky quality and filter used, I normally use 12nm filters HA HB etc, but when fullmoon is out and sky is dark blue than you need to go down to 6-7nm and maybe even down to 3nm, that's when it gets expensive tho. as has been mentioned your guiding has to be sorted for long exposures depending on the cam sensor and gain etc. also don't ignore the broadband filters from idas etc like the NB type as they have a good rep from imagers in japan.ton

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30 minutes ago, daemon said:

In principle I don't think it's a bad idea. I have a set of NB filters and am eager to use them but would say there are two things from my POV to consider:-

1) Guiding - you probably want long exposures for the subs, to gather enough data and guiding is likely to be needed to allow this. 

2) Target Selection -  sadly this is the blocker for me. The only viable NB targets worth imaging that I am aware of in the Northern Hemisphere at this time of year lie in the East and mostly around Cygnus (Elephant's Trunk Nebula etc) and as I have trees to the East I can't effectively image that area for long.

So, if you can see decent targets from your location and you can run decent exposure lengths, then maybe it is a viable exercise. For me - unless anyone has another suggestion - I think I will be sticking to broadband galaxy targets until conditions and target locations permit.

Happy to be corrected though!

Good luck!

daemon Steve

 

17 minutes ago, ebdons said:

Yes you can do NB imaging, depends on object magnitude ,sky quality and filter used, I normally use 12nm filters HA HB etc, but when fullmoon is out and sky is dark blue than you need to go down to 6-7nm and maybe even down to 3nm, that's when it gets expensive tho. as has been mentioned your guiding has to be sorted for long exposures depending on the cam sensor and gain etc. also don't ignore the broadband filters from idas etc like the NB type as they have a good rep from imagers in japan.ton

Thanks both for your replies. I have a set of Astronomik 6nm NB filters and my guiding is good 👍 .

I need to get some practice in with this new gear so I think I’ll give this a go (so long as I can find a suitable target).

[ebdons]

Hi, the only object I have imaged in 6-7nm recently is the cresent neb in Cygnus as it fits my cam ccd size (sx825m) and is a good magnitude (7.5) and you should get a good result using astronomic 6nm and is pretty good even with the 12nm versions. clear skies!