We haven't covered this topic in awhile so I'll post some new and old websites to help you along.
I like the pdfs that are downloadable. I print them out and keep them in a binder in the mh with my DO equipment.
Lodge DO Baking Temperature Chart. KEY: On the ***** line, the bold number is charcoal bricks for the lid, the /# is the number for the bottom.
Ex:
10/5 means 10 charcoal bricks for the lid, 5 on the bottom under the DO.
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Dutch Oven Dude has a very informative website including a briquette calculator (not downloadable).
Dutch Oven Dude's Website
"The only time you should fear cast iron is if your wife is fixin' to hit you with it."-Kent Rollins
First law of science: don't spit into the wind.
Magnus