http://www.iceinspace.com.au/index.p...63,500,0,0,1,0
Here I use the Baader micro focusser and T ring( T2 to1¼” micro-helical (4mm travel) focuser #BA2458125).
With an Oly Zuiko 50mm lens. There not much space between the back lens element and focus so you really need a short nosepiece (and IR filter) on the webcam.