Ah all good. Some species can vary quite a bit, but generally temperatures, both ambient and belly determine the metabolizing rate.
Ambients at 85 - 88 show a dramatic increase in both frequency and size of defecation, than say ambient of 78 - 81.
Small numbers to us, quite large to snakes.
Generally most snakes synchronize their defecation with the shedding process. To leave behind a smaller 'print' on their surroundings. Generally a substrate and enclosure that is cleaned less frequently will result in less frequent defecation too.
Anywhere between 4-8 weeks is considering pretty 'normal'. Some more frequently some less. I've known snakes to defacate in smaller quanities shortly after each feeding like clockwork. And some to defecate purely when they shed. It's pretty individual, taking husbandry into consideration.