A light bulb just went on. The 5D Mk II's pixel pitch is 6.4um.
Perhaps that's where CH got his choice of 0.006mm for the CoC... the CoC
is chosen to fit within the pixel diameter. Makes perfect sense.
Now, re-reading CH's post I see that he used 5.5 (vs 5) meters as the
focus distance and says that one can not differentiate between that and
either 5 or 6 meters since it fits within the DoF of 4.74 - 5.56 meters.
He also used f/2.8 for his calculation but I'm prepared to allow use
of f/3.2 on the DZ zoom.
If I now use 0.005mm as the C0C for the L1 (to fit within 5.6um) and use
f/3.2 at 5 meters I get DoF of 4.4 - 5.79 meters. Focusing on 6 meters
I get DoF of 5.15 - 7.18 meters. That says the L1 might actually be
able to do it but it sure is a close-run thing and requires that the
liveview shows pixel resolution which I'm not sure is true. Of course,
the lens also has to be perfect. An awful lot of ifs.
Chuck Norcutt
Ken Norton wrote:
>> I'm not sure if 5D II has poorer liveview than L1 but based on the DOF
>> calculator:
>
> Another thing to consider in this, which reinforces Chuck's position,
> is the pixel-pitch of the L1 is 5.6um, whereas the 5Dmk2 is 6.4um. For
> comparison, the 5Dmk1 is 8.2um.
>
> Based on this, the L1 does allow for greater focusing accuracy, but in
> that regard, the 12mp sensors of the newer Olympus and Panasonic
> cameras would be even better. Therefore, the L1 does have better
> liveview than the 5Dmk2.
>
> ;)
>
> But none of this compares to a split-image or rangefinder focusing aid
> (when calibrated).
>
> AG
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