When I was browsing the online gallery at wikipaintings, this one painting of Edward Hopper (Summertime) really jumped out, so I decided to use it for a study. It has all the elements. Rhythm in lines. Emphasis, a person (soft round lines) amidst a architectural background. Variety in clothes and curtains against brick and mortar. Economy in using white for the brightest lit areas. Repetition and continuity, the spacing between tiles. Balance in the woman standing in the middle.
I was experimenting with brushes and measuring methods so it took me waay more than one hour (+2 or so) to finish it. For the building I used a 100 x 100 reference grid. For the person a 20 x 20 grid on a separate layer. Pastel, hard square brushes and the eraser were used.