After my first two attempts(one for each grain filter)I gave up-realizing as you've pointed out that there are better ways,but hey I'll give most anything a chance at least once.I'll have to look into the poly filter-it would be easier-it is a bear screwing on a filter with fingerless gloves in ten degree weather.I find the 29 red to be good in most situations also,but with maco 820c and konica if the weather is overcast or cloudy with little to no sun I find the best negs come from the 89b.Actually in my opinion its when konica750 comes into its own.