East Boothbay artist and writer Don Dilworth will discuss and sign copies of his new book “Impressionism Today: a Painter’s Guide to a Timeless Genre” at Sherman’s bookstore in Boothbay Harbor on Saturday, Aug. 18, from 1 to 3 p.m.

This book is the fruit of 50 years of trying to figure out “How did they do it?”

As a student in the late 1950s, Dilworth was so impressed by the paintings he saw in the Boston Museum of Fine Arts – especially the impressionist works by Monet, Renoir, Cézanne, and others – that he set about trying to solve the riddle. Little by little, making slow progress, and making every mistake that a novice painter can make, he started seeing the glimmer of quality in his paintings.

One insight led to another, and after many years, many poor paintings, and occasionally a rather good one, he found a pattern in what works and what does not. Today his success rate is high enough that he felt qualified to write this book, hoping that other potential or practicing artists would find many of the succinct and pithy tidbits of advice to be just what they need to help them master their own art.

Discussing the quality of the artwork produced by local painters, as seen at craft fairs and in some local galleries, is a sensitive issue to the artists, and, while trying not to offend anyone, he observes in all honesty that those works are generally very disappointing. It doesn’t have to be that way. It’s not that the artists have no talent, since many of them very likely do, but rather they just don’t know how to go about it. They set their sights too low. He advises any artist who is proud of his work to take it to Boston and hold it up next to a masterpiece. That is the acid test, not of the painting, but your talent as an artist. If you can see that your picture is nowhere near the quality you see there, that means you have talent and will very likely produce excellent work if you go about it right.

This book tells you how to go about it. It discredits some common notions about art, such as the idea that your goal is to “capture the subject.” Nonsense, says Mr. Dilworth. Your goal is to make a great painting, and the subject is just the starting point.

Here is a quote from the book:

“Suppose you are doing a picture of a cat. A naïve person would say that the only reason the paint is there is so you can see the cat. I disagree completely. The only reason the cat is there is so I can show you what I can do with paint. The subject of a painting is paint.”

He will be happy to discuss this and many other insights from his book to interested people at the event on Saturday, Aug. 18, at Sherman’s Bookstore in Boothbay harbor.