Excited By a TV???

[Jeff Cashdollar]

Mike.

Correct, thanks for the peer review. Doubling the FL increases subject size by a factor of four, that is correct when you consider there is a 50% increase with a 100MM increase (500M = .56 larger)

I was thinking one thing and doing another. I did the math wrong and feel bad, usually thorough about this stuff. I will blame my wife, she is hurrying me to a wedding.

Another fun math fact while we are at it- the focal length divided by .50 produces the magnification power. Hence 400 /.50 = 8 (8 power binoculars) and 500/.50= (10 power) 10/8 = 25%. I know the 25% fit in there some where.