

ps- I used whatever I had on me (some old color oil pastels) and had the boy pick up a few chalk and charcoal pastels just so we could play with some options. That way you can take the extra step of stepping back and checking the accuracy of your shape before adding in all your painful detailing. I suggest using a color not so bold at first, something that might be close to street color but still distinguishable.

It takes a LOT of chalk and chalk dust to fill that in- the good thing is that this image is meant to be seen from standing distance so already your eye will do some filling in as well (most 3D anamorphic street artists seem to use sidewalks or large plaza settings with smoother stone surfaces).

If you're using a street like I did, up-close you'll see those valleys between the little bumpies become enormous.
