Canon Patent Application: Major Defocus improvements

[koenkooi]

Interesting idea! Indeed, that could give the system a bit more microcontrast by augmenting the depth-of field and therefore improve the guessing in which direction it should try to focus first. But I can't imagine that Canon's engineers did have that idea, too. Maybe there is another problem we do not see here...

Loss of light and flickering in the EVF come to mind.

 

[justaCanonuser]

Loss of light and flickering in the EVF come to mind.

Not, if the AF system just briefly closes the aperture to gain more depth-of-field, and then open again before the image is taken. So that would only part of the measurement process, not of the exposure itself.

 

[koenkooi]

Not, if the AF system just briefly closes the aperture to gain more depth-of-field, and then open again before the image is taken. So that would only part of the measurement process, not of the exposure itself.

That would cause either a blackout or duplicate frame in the EVF, not something you want if you are trying to track something.