David: No intention of being belligerent here, but (assuming for a moment) that Phase One and Hasselblad are creating somewhat equivalent products... in the video Michael states that he runs into trouble using autofocus with his Phase One/ Mamiya camera and the P65+ back, to the point that he uses the Mamiya 2X magnifier on the viewfinder and a microprism focusing screen to ensure accurate focus. Are you saying that such focusing problems don't exist with the H3DII-50 for example? I don't mean to put you on the spot, but I'm sure others would like to know as well.
Mike.
Well, it is very nice of Michael to say he has autofocussing issues with his P65+. ;-)
I do agree though that focussing accurately
manually can be a challenge so I assume a 2x magnifier would help. I did not sit through the whole video so I am not sure in which context Michael's comments were made.
Anyway, yes please do put me on the spot!
We recognised a few years back that as the resolution of sensors began to increase, the precision of the system was much more important. Not just the focussing but also things like fitment of the digital back to camera had to be tighter, flatter for example with a lower tolerances of error. Even minor things such as the flatness of the IR filter glass can cause issues!
Film and smaller sensors (think 16MP) were very good as masking inefficiencies in manufacturing, larger (think 50 / 60 MP) are very unforgiving!
With the 16MP we had virtually no complaints of focus errors but as we began to introduce 22MP and more so 39MP we saw the need for some changes to protect for the future.
The 'mechanical' method was solved with the Imacon backs by supplying shims to adjust back position to film / sensor plane. The smallest shim is only 50microns and this WILL make a positive difference to focussing accuracy. So you can see how important precision really is.
The beauty of controlling all parts of the camera system is that as well as tightening up manufacturing tolerances we also have a large amount of data from all these parts which again can add more degrees of accuracy.
So as I mentioned above every camera is custom calibrated in final production with regards to focus precision. Then further accuracy is achieved by correcting aperture dependent focus shift.
In summary, as we manufacture all parts and have all the necessary data AND the ability to communicate all useful data (The camera parts are 'networked on a databus) we can make incremental steps in increasing precision.
So after my long winded reply I would absolutely say I don't believe there are auto focussing accuracies with the H3D. It would be nice to have multi AF points but we do what we can!
....and for those reasons I would not say that Phase One and Hasselblad are creating somewhat equivalent products.
Best,
David