SkvLTD
Senior Member
So I remember an older thread where someone was asking what this thing did since his lens wouldn't mount quite right due to it being there-
I accidentally figured this out the other day and thought I would share- its a trigger made for AI-P/CPU lenses that tells the camera that the lens is set to the minimum aperture. When the body controls the aperture, typically the lens will be fully closed when off body and Nikon seems to have designed the bodies to have the minimum ap as default.
TL;DR- camera won't work if the cpu lens does not press this notch it with a special ridge on the aperture ring, or unless you tape/prop it into pressed position.
I accidentally figured this out the other day and thought I would share- its a trigger made for AI-P/CPU lenses that tells the camera that the lens is set to the minimum aperture. When the body controls the aperture, typically the lens will be fully closed when off body and Nikon seems to have designed the bodies to have the minimum ap as default.
TL;DR- camera won't work if the cpu lens does not press this notch it with a special ridge on the aperture ring, or unless you tape/prop it into pressed position.