52mm filter does NOT fit 2" filter wheels with 48mm filter threads! This is a larger filter with 52mm threads. The 48mm filter will fit 48mm aka 2" filter threads.

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  • 10nm bandpass for Ha and OIII respectively.
  
  
  • IDAS-proprietary “flat-top”, “steep cut-off” and “off-center” design eliminates the emissions’ signal loss due to the spectrum shift until F2 speed.
  
  
  • Available 48mm and 52mm mounted (2.5mm thickness)
  
  
  • No IR blocker required
  
  
  

IDAS NBZ Filters are designed to enhance the contrast of Hα and OIII emission nebula, yet accommodate the filter spectral shift when used with modern fast optical systems. This dual-band filter is ideal for one-shot color cameras as well as mono-color astronomical cameras