Hi,
I've bit the bullet and bought an F5 last Friday. Love the camera, lots.
However, I'm really wondering about the dynamic AF of the F5. Either I
have ridiculous expectations of it, or it just doesn't perform, or my F5
is a bit faulty. I understand that the active AF sensor does not change
in the viewfinder, but I really can't seem to get it to hand over focus
to another focusing point at all! It works maybe in the best of
conditions, once in every 20 attempts or so. I have the camera set to
continuous AF, focus priority, CH advance, dynamic AF, I've tried
various sensors as the active. Anything else I might be doing
wrong?
I spent quite an amount of time aiming at vehicles yesterday, just
playing around, and it was pretty obvious that in more than 90% of my
attempts the sensor did not hand over... or when it did it didn't hold
for long and would quickly re-focus based on the active AF sensor.
Basically I was at the side of the road , vehicles coming right to left,
with the right AF sensor the active one. As the vehicles approached, I'd
lock the active sensor on them, and follow until they got large enough
to cover both the right sensor (active) and the centre sensor (passive),
then gradually I'd ease the right sensor off the vehicle, with the
centre, and usually the left, sensor, still on the vehicle, but the
vehicle would rapidly go out of focus. I'm pretty sure the active sensor
is locked onto the background most of the time, but usually I'm too
occupied watching the vehicle (go out of focus...).
I thought this might have been a contrast problem, but I think I've
tried it enough times on enough vehicles to eliminate that. Also, the
active sensor has no trouble with the same subjects... When I try it in
vertical, with the appropriate sensors, I can't even remember getting it
correct once! Any advice? I was using the 80-200/2.8 non-S. I tried the
vehicles around noon, and then again at about 5, so I doubt light level
is the problem.
I processed that roll of Tmax 100 later that night, and sure enough the
negs confirmed my impressions. For the first few negs the vehicle was
sharp, but the moment the vehicle left the area that approximately
corresponded to the active AF sensor, the vehicle would go all blur on
me...
Another thing is, I ran a roll of slides through the camera shooting
soccer, and I had a few action shots where NOTHING is in focus. No, I'm
100% sure it's not camera shake. The slides were not even sharp on the
light table, let alone under a loupe, and my shutter speed was easily
1/250. I was on a monopod, and sometimes I saw the shutter go when the
image in the viewfinder wasn't sharp. Originally I thought it was
because one of the other 5 AF sensors were locked onto something else,
but looking at the slides... nothing was sharp. It was on CH, with focus
priority set as a custom function. I tried aiming at an un-AF-able spot,
like the sky or a white wall, and sure enough, the shutter doesn't trip.
Any ideas?
Thanks in advance,
Jed
--
_______________________
An election is coming. Universal peace is declared, and the foxes have a
sincere interest in prolonging the lives of the poultry.
-- George Eliot, "Felix Holt"
