Shades of Bright and Dark on the Moon

I made two observations about a week apart to compare the brightness and darkness of the moon. The Brightest features of the moon that stayed consistently bright was the center of the moon. It always stayed a glowing yellowish, cream color.  The maria that was the darkest was the sea  of rain and the sea of storms.  The most delicate patches of shading on the moon was wear the sea of serenity and sea of tranquility would be.  Keep in mind this is just what I saw with my naked eye. Below are sketches of what I found during my observations...