I think Erik might have misconstrued (or thinks others might misconstrue) some comments I made on another thread where I implied that in certain circumstances, with certain scenes that require a specific DoF and fast shutter speed, the very cheap Canon D60 might produce results that are of higher quality than the P65+, and specifically of higher quality in respect to DR, according to DXOmark.
Since DXOmark do not address resolution issues, there was some doubt as to whether or not the P65+, in sensor+ mode where the pixels are binned to 15mp, would produce higher resolution at F11 and ISO 1600 than the D60 would produce at F4 and ISO 100.
Erik maintains that the exceptionally large P65 pixel that results when each group of four are binned, would ensure that, even at F11 or F13, the P65+ would produce a sharper image than the D60 can produce at F4 with a lens like the 100/2.8 IS Macro which is sharpest at F4. In other words, Erik maintains that the undoubtedly better resolution of the Canon 100/2.8 IS used at F4 would not be sufficient to overcome the advantages of the significanly larger, binned pixels of the P65+ in sensor+ mode.
I would agree when comparing images from both cameras at base ISO, this would indeed be the case. However, I get the impression that the option of sensor+ is available only at ISO 1600 and above, but I'm not sure about this.
Here's a comment from Michael's review of the P65+.
http://www.luminous-landscape.com/reviews/cameras/sensor-plus.shtmlThe above frame and its accompanying 100% enlargement tell the story. This is a typical "event" photograph taken under available light. At ISO 1600 in Sensor+ mode the P65+ delivers a clean and usable 15 megapixel file. Close examination does show a bit of aggressive noise reduction in some areas of very fine detail, but this is only when compared to the usual totally clean files that medium format backs provide at lower speeds, and is no more so than files from contemporary DSLRs at a comparable speed.
I understand this comment from Michael is a general impression only. DXOmark show quite clearly that the Canon 7D at ISO 100 has almost 2 stops better DR than the P65+ at ISO 1600 in sensor+ mode. (1.87 stops to be precise). Not only is the DR of the 7D significantly better, but all the other image quality measurements addressed by DXOmark (tonal range etc) are also at least marginally better.
Now you might well ask why would photographers bother to use a P65+ at F11 and ISO 1600 at all? I guess the answer would be, because they are not carrying a good DSLR at the time.
In my own photography I find that I am often juggling the compromises and trade-offs between getting the degree of DoF I'd like and a sufficiently fast shutter speed to freeze subject movement and/or camera shake. For my style of phoptography, I prefer not to use a tripod, if I can get away without using one. I find tripods cumbersome and restrictive.
F4 at ISO 100 on the 7D (and presumably 60D) results in the same DoF and same shutter speed as F11 at ISO 1600 on the P65+. In fact the shutter speed on the P65+ would probably be slightly slower since ISO 1600 is really only ISO 698, according to DXOmark.
In a situation where the natural lighting is not strong and flash might be inappropriate, but a good DoF and reasonably high shutter speed is a requirement, it would seem to me the MFDB is actually at a disadvantage compared with the DSLR.
On the other hand, when the subject is still and one needs a very high resolution image, it's now very easy to stitch multiple images, even multiple, exposure-bracketed shots to increase DR and tonality in addition to increasing resolution.