I was wondering if anyone knew the exact ratio of Futura's perfect circle lowercase "o". In other words how much larger the "outer" circle is than the "inner" to make up the weight of the letterform?
Typophile
Futura Circle Ratio
After much struggling with math, I believe the correct ratio is 1:.625.
Then, you need to factor in the optical correction.
1.625 is almost exactly the Golden Ratio (1.618).
But be careful. The O in Futura is not a perfect circle. It's slightly wider than it is tall, at least that's what I see when I convert Futura to outlines in InDesign and then look at the W and H dimensions:
12 pt Futura by Adobe
Light
W = 0p9.383
H = 0p9.286
Book
W = 0p9.43
H = 0p9.358
Bold
W = 0p10.007
H = 0p9.647
interesting...
the reason I was asking...
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