Shooting in the rain is a pain in Winter Leauge FT, I drop at least 4/5 because of the varying amount on rain in the lense, or, tissue stuck to it via trying to wipe it. Do we know of a rain-cote type lense to fit my BSA, or, any good ideas on barstardising a Leup 28mm rain-cote lense onto a flip cover to fit my big BSA? Many thanks in advance!