Above is a photo that shows an effect which can be capitalized on when painting seascapes. Notice how some of the planes both large and scattered along the edges of the rock are reflecting the high key note of the light. That's what makes a rock look wet, that reflectivity. The mass of the rock is quite dark and often gets a blue value across the top, as I pointed out the other day. Now its easy to observe this in the photo. But if you paint this effect in nature and photos and learn how it works you can make it up. You can also install it into a made up painting or add it to rocks in an observed one.
Above is a section of a Waugh using this effect. The planes in the rock facing us are in Stygian darkness, the planes facing towards the light are the rocks color, plus the color of the light. You need to always know both where the light is coming from and what color it is.
The turning edges between the light and the shadow are in highlight.
Its pretty simple. This little effect can be all over a seascape. The little spots of highlight also make crisp accents that enliven passages. All of that sparkle makes a passage lively rather than ordinary and matter of fact. Many effects in painting involve knowing where the light is coming from, what color it is and how the planes in the object are receiving that light.
Above is a painting by William Ritschel an important California impressionist. 1864-1949 Ritschel was an early member of the Carmel art colony, moving there in 1911 after the San Fransisco earthquake and fire. He painted many surf subjects. Ritschel had a home on the water and spent a great deal of time observing the sea and its moods.
This Ritschel is from the Springville Museum of art in Springville, Utah. That's a pretty unusual view of the sea but there are many paintings from the historic Carmel art colony that painted angles like these. Many were done at Point Lobos.