Using 7nm dual-band Ha/OIII filters on fast f/3.8 systems

Equipment CMOS Filters Refractors Duo-Narrowband H-alpha Narrowband OIII Optics Help Needed
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Interactive Sky avatar
Interactive Sky avatar

Hi all,

Quick question: has anyone used ~7nm dual-band filters (Ha/OIII) on fast systems (f/3.8)?

I’m just checking if that could work with Askar 50P.

  • Does bandpass shift become a problem?

  • Is 7nm still usable, or should I look at high-speed filters?

Thanks! Clear Skies!

Well written Respectful Engaging
Tony Gondola avatar
Tony Gondola avatar

https://deepskydetail.shinyapps.io/Bandpass_Shift_Calculator/

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