i could,nt tell you the butter2weed ratio because i really just wing it everytime.
but what i do is just collect all my trim and small popcorn buds straight from the plant into a plastic container then i put it in the freezer. then i put a pan of water on the stove and warm till boiling. once boiled i turn off the heat and let the water stop bubbling.then add one stick of butter (approx250g) and let it melt slowly in the warm water .once the butter is melted add your trim and mix it all together. then turn the heat back on and bring too a real light simmer for 6 hours. the key is too add water every 15-30 minutes because it will evaporate. i like to make sure mine has alot of water in the pan at all times so that the butter does,nt burn.
next i put a seive over a large glass bowl and poor the mixture thru it pressing all the green down to get all the butter out (there will be alot).i then cover the bowl and put in the fridge over night.
next morning i just lift out the disk of butter scrape the nasty off the back, dab off the excess water with kitchen cloth. and your ready too cook.
hope this helps man