nishan87uae

I have a 5d mk3 and a d80 and interested in getting into wedding videography. My main concern is the lack of redundant recording option in both cameras. Currently I am looking at getting 2 blackmagic video assist 5" recorders for both cameras (with cages) Is it possible to do redundant recording with mk3, d80 and bmvas? Otherwise what are the options available? thanks in advance