I post too Much on Here!!
- Jul 21, 2010
You keep using the word precise or precision when you mean accurate or accuracy. Precision is repeatability, accuracy is closeness to true. An AF system that focuses on exactly the same spot 50 times in a row is highly precise. If that spot is 2 m behind where the camera is supposed to focus, the AF system is not accurate.What makes you think so?
Groups of pixels are used for DPAF, you’re never going to get pixel-level accuracy. FYI, the Canon patent has double rows.I have never claimed it does.
However, when you only sample every second pixel in the vertical direction for the vertical phase difference, you shouldn't expect to be able to achieve pixel-precise focusing on horizontal lines in the general case.