QUOTE(jchue73 @ Jul 16 2011, 12:28 PM)
f/1.4 at 85mm is very thin DoF. The camera may think it achieved focus but that's what the camera thinks. I'm sure that in your shooting, you'd find almost 50% (if not more) of your shots even though nice but when viewed at 100%, it locks on a different body part rather than the intended eyes.
In this respect, both 1.4D and 1.4G will achieve the same results because focus is determined by the body.
I will only go so far as to say that the
speed of focus acquisition, the AF-S will acquire focus faster but in terms of focus accuracy, that's pretty even since it's on a same body. For non-action type shooting, you can take all the time to lock focus. Faster or slower, you'll still achieve it.
Focus hunting? Yes the D lens will hunt and because it's slower, you'd think that it hunts a lot. The AF-S lenses also hunt but they recover faster since the motor is fast and hence less frustrating for the user.
Partly true but it would depend on the type of body. But from the back of mind, you can mount G lens on newer film bodies but would only work in Aperture mode.
Okay let's get to basic first.
1. If I understood your reply, you assumed I or my friend uses 'Area mode' AF tracking when comparing the 85 f/1.4D versus the 85mm f/1.4G?
2. 50% that my shots are OOF? Meaning not focused to where I intend to? I get it focused where I want it to be. I shoot only in single AF point mode. If it is the eyes, then it is the eyes.
3. Based on my experience with the 85 f/1.4D, it acquire focus faster than the 85mm f/1.4G. But hit rate aren't as good as the f/1.4G despite being faster.
4. Depending on condition, sometimes the 85 f/1.4D can't even get a lock under low light, hunting compared to 85mm f/1.4G. To be frank, have you tried the 85mm f/1.4G and comparing it side by side with the f/1.4D before? If you did, you would understand what I experience.