Setting up Canon EF 300mm f/4.0L IS USM with 7D.
- Thread starter thebullet
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I heard about this! so, what setting would you suggest and it may sound silly, but how would I know that the focus is spot on?
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Initially I would pick a nice contrasty static object and see if the focus is OK, if so I would forget about it. If not you then need to calibrate. Generally I've found my Canon lenses haven't needed micro AF, only my 3rd party Sigma and Tamron ones so hopefully you will be fine 
You might also find that slowing down the AF tracking speed helps with getting consistantely in focus shots when using AI Servo. This isn't the speed of AF but rather how quickly it looks to aquire another target and when set too fast makes things jumpy. I'm usually on the lowest or 2nd to lowest with both my 7D and 1DmkIII.
You might also find that slowing down the AF tracking speed helps with getting consistantely in focus shots when using AI Servo. This isn't the speed of AF but rather how quickly it looks to aquire another target and when set too fast makes things jumpy. I'm usually on the lowest or 2nd to lowest with both my 7D and 1DmkIII.
Initially I would pick a nice contrasty static object and see if the focus is OK, if so I would forget about it. If not you then need to calibrate. Generally I've found my Canon lenses haven't needed micro AF, only my 3rd party Sigma and Tamron ones so hopefully you will be fine
You might also find that slowing down the AF tracking speed helps with getting consistantely in focus shots when using AI Servo. This isn't the speed of AF but rather how quickly it looks to aquire another target and when set too fast makes things jumpy. I'm usually on the lowest or 2nd to lowest with both my 7D and 1DmkIII.
Thanks for this and when you say it makes things jumpy when it is too fast, what do you mean? atm when focusing sometimes the whole viewfinder moves about which is weird. I will have a place.