I'm new to the forum, and hope I can find some help. I just purchased an SWC/M from the mid 1970's (Carl Zeiss Biogon 38mm f/4.5 lens) and would like to purchase a polarizing filter for it. I understand 63 mm is the size I need, is this right? Can anyone tell me the adapter I would need for it? Finally, is it correct that I cannot mount a hood and adapter at the same time? Thanks in advance for any help.