Dendochronology: reliability and calibration

I found more tree rings in the Aber Valley in north Wales. Pete found this website for me https://www.environmentalscience.org/dendrochronology-tree-rings-tell-us - thank you! I think this tree will be oak which they say is the most reliable in terms of producing a ring every year. It works well on the first picture. I can count the correct number of rings between the dates. Even with the real tree in front of me, I was struggling with the first 100 years. I was interested in the idea that the growth cycle of one tree can be matched to records from other trees and the attempts to calibrate the dating against radiocarbon dating.