Singapore Ice Hockey

[mervin420]

most of the time? i'm used to AI Servo ALL the time

Hi Sehsuan,

Recently, I am trying out AI Focus and AI Servo quite a lot in recent events. The main problem is sometimes it 'misfocuses' especially on my 70-200mm f4. Even when the subject was stationary and it kept focusing on the wall behind.

Is there something to do with back/front focusing prob? Or maybe some strong spotlights which are around to cause confusion to the focusing? Perhaps if you can give me advice?

what I do is that I only use only the Centre focus point to focus in AI-SERVO. This is to prevent excessive hunting of the lens if you use all your focus points. The AI is not 'smart' enough to calculate yet which is suppose to be the point of focus if you use too many points. If you shoot with fixed zooms like 300mm, 400mm etc, use manual focus.

 

[Wlyang]

what I do is that I only use only the Centre focus point to focus in AI-SERVO. This is to prevent excessive hunting of the lens if you use all your focus points. The AI is not 'smart' enough to calculate yet which is suppose to be the point of focus if you use too many points. If you shoot with fixed zooms like 300mm, 400mm etc, use manual focus.

I have tried shooting last night and find the same problem on my 70-200mm. AI-SERVO with focus point shifted to the extreme right, camera tilted to vertical position to autofocus on the face. Many of my shots tag sharp at the bottom but seems out of focus from the top(face) where I'd focused. Even when models are stationery, getting the accurate focus seems to be a challenge. :sweat:

I am beginning to suspect my lenses/camera suffering from back/front focusing problems. :think:

 

[loso]

http://www.hksp.org/Gallery.php?L=E&SubID=34

let's take a look;p