Does anyone know what filters will fit the Ocusync Air Unit camera?  The OD on the lens barrel is 16.5mm.  I tried the Mavic filters and they don't fit.  The ID on the Mavic PolarPro filter is 20.0mm.  Maybe I can 3D print an adapter. Any thoughts?
  Any thoughts?
	
		
			
		
		
	
				
			 Any thoughts?
  Any thoughts? 
				
		 
			 
										 
 
		 
 
		 
 
		 
  
  
  
  
  
  
 
		 
 
		 
 
		