August 22, 2014, 10:05:12 PM

Author Topic: Macro EF 100mm f/2.8L Macro IS USM  (Read 2377 times)


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Macro EF 100mm f/2.8L Macro IS USM
« on: June 15, 2013, 05:13:01 AM »

I found the the AF of the EF 100mm f/2.8L Macro IS USM is very slow when utilized under water.
I have tried different settings and the best way, for me, was to set the lens AF selector on 0.3 - 0.5 m
In the "full" position the time the get the subject focus ... it is gone.
Do somebody experience the same, or do I need to service my lens.
Any tip to get the full range of this lens underwater ?
I'm using this lens with the 5D3 and an Aquatica casing.




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Re: Macro EF 100mm f/2.8L Macro IS USM
« Reply #1 on: June 19, 2013, 11:25:49 AM »
Do you have any domes mounted or other front parts?
How good is the light you have? What is the camera "suggesting" for shutter, speed and iso?
On my last dive I was with my small Canon compact camera at 20-30 meters and had no problems focusing in daylight.
Is the focus hunting?
Are you using live-view or through viewfinder? (I guess live-view, which makes it much slower)
Does the focusing work fine on land inside the case?