Re: Pinhole f number

["Peter Jon White" <pjwhite@tiac.net>]

Thomas P Myro said,

the "appearance" of the
> aperture size by looking through the front element is a coincidence, and
> not indicative of anything, evidently.

I measured the apparent size of the apertures in 12 different lenses 
that I own. In every case, the measurement coincided with the 
aperture ratio of the lenses focal length. That's an awful lot of 
coincidences.

> 
> As to radius vs diameter, argue with Dr. Abbe, not me.

I can't argue with Dr, Abbe because I don't know what he said. I only 
have your interpretation of his writing, and I believe that there is 
an error somewhere. Whether the error is yours, or Dr. Abbe's, or 
your interpretation of Dr. Abbe, I have no way to know.

Peter Jon White