The max aperture on my Tokina 100mm at-x pro is f/2.8 but when I focus on anything closer than around 9 feet, the aperture automatically starts to close down and get progressively smaller (higher f-stop) the closer I get to my subject. Extreme macro shots result in the aperture being hard set to f/5.6
I realize the closer you get to the subject, the more shallow the depth of field, and that 2.8 is probably too large on macros, but I've never experienced where the camera deems the appropriate aperture (IN MANUAL MODE).
what's it doing? How is it determining this ideal f-stop? Thanks!
Nikon D610 by the way...