I got an EOS-M ad in the mail this morning from Canon. I can probably
live without really fast focusing but without the EVF I'm not a
customer. I didn't bother to open the mail.
Chuck Norcutt
On 11/3/2012 12:29 AM, Moose wrote:
> On 11/2/2012 2:57 PM, usher99@xxxxxxx wrote:
>> I just don't get this one. Perhaps Canyon's first toe in the water.
>> They don't really have an APS-C sensor to blow out the competition out
>> of the water and no EVF or articulated screen. It does nicely use Canyon EF
>> lenses
>> though with IS/AF but the AF performance is just not there.
>>
>> http://www.lensrentals.com/blog/2012/10/eos-m-first-impressions
>
> It seems that Canon's designers and marketers were caught in an impossible
> situation - and managed to bring a
> semi-functional compromise camera to market. Technically, the silliest thing
> to come out of Canon for a very long time.
> From a sales standpoint, who knows?
>
> When Roger says "If they fix the AF speed with a firmware update ..." It
> seems that he has already forgotten much of
> what he wrote about CD & PD AF in July 2010. Although now dated in some ways,
> it's still a nice explanation.
> <http://www.lensrentals.com/blog/2010/07/how-autofocus-often-works>
>
> The basic situation is that lenses designed for PDAF physically can't focus
> very fast on CDAF. The types of focus motors
> they have and the mass of the moving parts are ill suited for it.
>
> Pretty much everybody but Canon has been finding strategies to adjust to the
> change.
>
> Oly has jumped with both feet on the alternate of completely new engineering
> of lenses specifically optimized for CDAF,
> with very small, light moving elements and different motors. That they can
> claim the E-M5 to be the 'fastest focusing'
> something or other, and my personal experience, show that this strategy
> works. As a side benefit, they especially silent
> focusing for video. I assume Panasonic must be doing something similar,
> although their decision to go with in-lens IS
> may make it harder.
>
> Sony (and Nikon?) has designed sensors with a few special sites to do phase
> detection, allowing fast movement in one
> step to at least close to accurate focus with conventional lens AF
> mechanisms. I say 'close' because they do final focus
> with CDAF. Although they trumpet this dual mode as a positive feature, I
> suspect it is necessary because the on-chip PD
> sensors don't work as well as a full fledged DSLR PDAF system.
>
> This would be a great solution for Canon, allowing the EOS-M to use their
> huge array of EF lenses effectively. The
> reality of the EOS-M shows that they don't have a hybrid PD sensor chip
> ready. No firmware upgrade is going to change
> the basic problem.
>
> Just why the native lenses for the EOS-M are still slow, although not as
> badly so, I don't know. Perhaps the whole thing
> is just a stopgap measure until they bring out an alternate solution to
> mirrorless use of their EF lenses. In which
> case, they may have ported existing lens optical and mechanical designs for
> the new camera with the minimum redesign
> expenditure.
>
> CDAF Moose
>
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