View Single Post
Old 02-28-2013, 10:49 PM
  #3  
mclarkson
Super Contributor
 
mclarkson's Avatar
 
Join Date: May 2010
Location: Wichita, KS
Posts: 3,958
Default

I have checked it on several simple plans - white circle on black square, white triangle on black square, etc. etc. etc.

It seems to be dead on the money. The attached, for example, works out to 72%.

It's a circle inscribed within a square. The ratio of the surface area of a circle with diameter N to the surface area of a square of side N is about 78% (78.54).

Then there's a little square, 1/16th the area of the big one. 1/16 is 6.25%. 78.54 - 6.25 = 72.29. Photoshop reports 72%.
Attached Thumbnails Click image for larger version

Name:	test01.gif
Views:	134
Size:	4.4 KB
ID:	166657  

Last edited by mclarkson; 03-01-2013 at 12:25 AM.
mclarkson is offline  
 
Page generated in 0.04845 seconds with 13 queries