So if you want 4 times the light, you take the square root of 4 or 2.
16/2=8 f/8 gives 4 times the light as f/16
On Fri, Jan 21, 2011 at 7:53 AM, Lew Schwartz <lew1716@xxxxxxxxx> wrote:
Your mensa-like friend might do well to reflect that "f" numbers are
stated as reciprocals, so f/16 is actually much smaller than f/2,
smaller numbers = less light (f/16 being smaller than f/2). Other
ponderings about the area of the aperture opening are, however that
area is relative to the focal length of the lens in question (the "f"
part of the f number).
--
Kim Mosley
mrkimmosley@xxxxxxxxx
Website: http://kimmosley.com
Blog: http://kimmosley.com/blog
