Measuring food

ok I am sure that this has been asked before but I havent found a thread about it yet. I am switching from free feeding (dry only) to feeding twice a day i feed a small can of wet in the morning but im not sure how much to feed (dry) in the evening. so my question is measurment wise how much dry should i put out in the evening and should i leave it down for only a little bit or leave it out all night and take it up in the morning? i plan on asking the vet monday when i take merlin in for his first check up

You'll have to go by the feeding recommendations on the bag, as the amount really depends on the brand. I feed Jamie canned in the evening, and 3o grams of dry food in the morning (1/2 the daily ration). I use a postal scale to measure the amount. He generally eats all of it in anywhere from 5 to 30 minutes.