I work on the computer in Photoshop to explore variations in the grids I draw - Easy, fast and intuitive. I  don't over-think, and edit after the fact. The possibilities are endless, but I try not to be daunted by that fact. Many of these will never be drawn on paper , but engaging as a series.
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| Working from the Center | 
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| Working from the Top | 
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| Adding a Darker Element |