Never saw your post. Wave bigger next time.
I would have suggested changes to his explanation of adjusting enlargement and reduction by 'simple' formula. The formula blew my mind. I understand the formula. I'm getting deja vu, I think we have had this discussion.
I think relating this concept visually to the well know studio lighting formula inverse square of light would have been good for visual learners. Perhaps the traditional cone of light?
It's nit pick, and too late now.
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