Mildew on maples

I was worried about the mildew that appeared on the maple leaves earlier this year and was relieved to read an article early in August that "The superficial, fine-powder-like mildew is caused by Erysiphales fungi, especially Podosphaera xanthii. Infection can happen year round, but the fungus seems to favour moderate temperatures and high humidity, similar to greenhouse conditions. All maples are susceptible, and other plants can also fall victim." (Times Colonist E-Edition, Aug 9)  According to a professional botanist, the mildew will not cause long term damage. Phew!
I finally took a photo of these leaves today to document the mildew.