The video shows how artists enlarge and copy from photographs. First grid lines are drawn on the reference photo. Then grid lines are drawn on the paper with enlarged or reduced grids. Now draw the lines from the reference photo to the drawing paper one square at a time. Now complete the outlines from the reference photo. Erase all the grids and you have only the outlines. Add details and area of tone. Darken the dark areas and you have a replica of the reference photograph. The same technique can be used for any other drawing.
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