Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Canon EOS dSLR

Thread Tools Search this Thread
Old Mar 16, 2007, 9:30 PM   #11
Senior Member
NHL's Avatar
Join Date: Jun 2002
Location: 39.18776, -77.311353333333
Posts: 11,331

nymphetamine wrote:
Can u please elaborate on ur method of achieving the focus with single AF so i can try the same. I just got a 1D Mark II. Havent got it yet, but just purchased.
JohnG nails it right on the head: "... as long the bird stays within that DOF area, there is no need for predictive focusing. If you get a good focus lock the first time, the subsequent shots in the burst will still have the subject in focus. You simply re-aquire focus yourself every so often."
-> The rear button only allows you to alternate quickly between the single AF points vs the other 45 so you always have this two options at the ready with your thumb. The shutter release still controls the actual focusing when 1/2 pressed so when you achieve a lock just release the shutter all the way - if not you can re-acquire by 1/2 pressing the shutter again...

This technique solves two problems as JohnG described: First"... as the first shot in ai-servo being shutter priority" you are not always going to get a perfect (spot-on focus) the 1st time around but must rely on subsequent shots (which are focus-priority instead) when the camera track on the subject - but because the subject is so small in flight you run into the 2nd problem: "...mis-focus issues when servo gets tricked by another object (branch) or you can't follow the subject and the focus point(s) fall off the subject."
However; also be aware here that even though the camera is on focus-priority for the subsequent shots, the focusing will still time-out to keep the frames rate up so you can still end up with out-of-focus pictures following a burst - and why there's several level of priorities for settings how the camera should be bias on the 1D in the Custom Function (i.e. more accurate focus or more fps...)

BTW this should work the same on the 5D or any other Canon dSLR (at least my 10D did it too)

NHL is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -5. The time now is 8:53 AM.