At 05:13 2/16/00 , Paul Wallich just wondered <g>:
>Am I right in assuming that the number of points in the flare around
>a light source is indicative of the number of blades (or more precisely
>the number of corners) in the stopped-down diaphragm? I have some nice pix
Yes! A couple photos on my site are classic examples of this:
http://members.xoom.com/_XMCM/johnlind/olympus/olympusgallery/om42.html
[six blades in the 35/2.8 Zuiko PC shift]
http://members.xoom.com/_XMCM/johnlind/olympus/olympusgallery/om46.html
[eight blades in the 50/1.4 Zuiko MC]
Small bright point sources of light will show this unless you are wide
open. Much more prevalent in night photos such as these than during
daytime. It's caused by diffraction at the edges of the aperture blades.
Won't happen wide open because the "hole" is round.
-- John
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