Ever bathe in color? Porter and Meyerowitz created ethereal seascapes and landscapes infused with light in all its hues. We will look at these for the pure joy — and also to understand why photography’s transition from black and white to color was a watershed in both its acceptance as art and ascendence as a prime vehicle of communication. It doesn’t hurt that these masters’ focus was on two beloved locales: the Maine coast and our own Cape Cod.