https://prod-edxapp.edx-cdn.org/assets/courseware/v1/7ce53cae91cedf7d9263af41ced9e195/asset-v1:SmithsonianX+NGA1.1X+1T2019+type@asset+block/Shari_Tishman_Slow_Looking_Ch1p4-7FINALWM.pdf

https://prod-edxapp.edx-cdn.org/assets/courseware/v1/00f7ef01911e55f5f3f1ca6f7ea1c32e/asset-v1:SmithsonianX+NGA1.1X+1T2019+type@asset+block/Shari_Tishman_Slow_Looking_Ch2_p26-27FINALWM.pdf
SLOW LOOKING