Royal Noble Consorts and Concubine's rank

This is the side effect of watching historical drama. I love to know more about culture and the beliefs of Korean people during Joseon Dynasty... So, I made some research and found out the ranks of King's women.

rank	romanization	hangul	hanja
Rank 1A 정1품	Bin	빈	嬪
Rank 1B 종1품	Gui-in	귀인	貴人
Rank 2A 정2품	So-ui	소의	昭儀
Rank 2B 종2품	Sook-ui	숙의	淑儀
Rank 3A 정3품	So-yeong	소용	昭容
Rank 3B 종3품	Sook-yeong	숙용	淑容
Rank 4A 정4품	So-won	소원	昭媛
Rank 4B 종4품	Sook-won	숙원	淑媛

For the rank of Bin, the King or Queen consort would attach a prefix in association with the character /personality of the Royal Consort, such as Hee Bin (Hee = Radiant), Sook Bin (Sook = Clarity/Purity), Ui Bin (Ui = Appropriate/Fitting), and so forth. However, they are all of the same rank "Bin" so they are all of equal rank.