12mm 5.6 Ultra Wide Heliar with filter adapter
12mm 5.6 voigtländer ultra wide heliar filter adapter
filter_adapter_voigtländer_12mm_5.6
12mm 5.6 Ultra Wide Heliar with filter adapter
12mm 5.6 voigtländer ultra wide heliar filter adapter
DIY……..
49mm rubber lens hood (to slip over lens barrel*)
Peel off the rubber
Add a 49 to 77mm filter adapter
Voila! Total cost < $20
* May need to fettle (wet&dry paper) the inside of the hood so it slips over the lens, or add a piece of tape to the inside if it's too loose.