06-07-2012, 03:35 PM
[quote name='Brightcolours' timestamp='1339073516' post='18741']
USM does not react fast enough for the small steps contrast detect needs. It is not about speed but the way the motors are being used. USM is fine for PD AF use, where the motor does not have to stop moving for focus check.
As I said, this is the reason Olympus uses MSC motors in the contrast AF based MFT lenses, and not the SWD motors (USM clones) they used in PD AF DSLRs.
http://www.olympus.com.au/Learn---Explor...ology.aspx
[/quote]
I suppose that contrast AF applies for motion picture recording? That new Canon body seems to emphasize motion picture recording ability with it's stereo microphones?
USM does not react fast enough for the small steps contrast detect needs. It is not about speed but the way the motors are being used. USM is fine for PD AF use, where the motor does not have to stop moving for focus check.
As I said, this is the reason Olympus uses MSC motors in the contrast AF based MFT lenses, and not the SWD motors (USM clones) they used in PD AF DSLRs.
http://www.olympus.com.au/Learn---Explor...ology.aspx
[/quote]
I suppose that contrast AF applies for motion picture recording? That new Canon body seems to emphasize motion picture recording ability with it's stereo microphones?