Re: Auto-focus on digital SLRs.

In article <6q%vj.40567$w57.25437@[EMAIL PROTECTED]
>,
 "Dudley Hanks" <hanks.dudley@[EMAIL PROTECTED]
> wrote:

> "____" <internetphobic@[EMAIL PROTECTED]
> wrote in message 
> news:internetphobic-63B1EC.12595123022008@[EMAIL PROTECTED]
> > In article <kkd0s3h7vjcej95rfvbgjk5naq980trj1s@[EMAIL PROTECTED]
>,
> > Steve <steve@[EMAIL PROTECTED]
> wrote:
> >
> >>
> >> A crank starter sure would be nice if you accidentally leave your
> >> lights on.  And if the engine is too big to crank start, one of those
> >> clockwork wind-up crank starters would work great.  Just like manual
> >> focus can work great if the autofocus isn't doing what you want.
> >>
> >> Steve
> >
> > Good point, to place back in context any suggestions for speed
focusing
> > rings for manual control?
> >
> > -- 
> If you really want to go that route, you could always place an object at

> various distances in a well lit setting, and then autofocus on it. 
Scribing 
> a reference line at some point of the housing and a small mark on the 
> focusing ring could help.
> 
> But, after playing around with a Rebel XT and trying to get it to
exhibit 
> similar behaviour, I have to say it actually is quite good.  The only
time 
> it would hunt around was when I was pointing it at a white wall, or some

> other nondescript object with no texture or detail.  If there is
something 
> to work with, the AF unit seemed to find it.
> 
> Also, if the AF unit couldn't find anything to focus on, it only went 
> through its range twice -- once rotating out and once coming back in. 
It 
> took about a second, and it wouldn't try again if it wasn't initially 
> successful.
> 
> Does the problem get worse as you zoom out?  If so, it could be the
result 
> of the variable aperture of the zoom lens.
> 
> How old is the camera?  Could the sensor be dirty?
> 
> Lastly, it is im****tant to keep in mind that red-eye reduction features
tend 
> to slow down camera operation in low light situations.  The camera might

> hunt a bit for focusing, and then sit there for another second with the 
> red-eye reduction light eluminated even if you don't need it.  This
might be 
> mistaken for slow AF performance.
> 
> I don't know if any of this applies, but it doesn't hurt to mention it.
> 
> Good Luck,
> Dudley

Good advise however does not apply directly - because mine is a speed 
issue, doing at a wedding etc. I need better focus quickly and see the 
down side of AF compared to manual focusing.

-- 
Reality is a picture perfected and never looking back.