the thing with a filter its not all about dimming the light etc its that you can pick an eye up alot better,you get rabbits squatting out in stubble ect they take some spotting without one, with a filter on if its out there youll pick it up, myself could never lamp without one, i find by leaving it till the last sec as the dog gets out to the bunny then flicking it of the dog alot of the time can get very close before the rabbits lifts but everybody lamps different and what works for one wont for another