And one of those limitations goes something like "adequate DoF in macro equals unsharp pictures".
Thanks A49 for your quite clear answer. Yes the question was not really on-topic, but there are already two resolution-related threads on APUG (and at least one on DPUG I found out).
Marco, I did not post it on DPUG because it really was about resolution and its visual perception. If you just substitute PPI with the equivalent lp/mm my question remains the same.
I'm one of those giving priority to the sharpness, not for other reason that it will give you an idea of how much you're are loosing from the original image in front of the camera. I believe the need for sharpening in PS is an indicator that something is wrong in the path.
Let's not forget that Photoshop's 'unsharp masking' command is a copy of a manual process, called 'unsharp masking' and has been used in analog photography decades before Photoshop was conceived.
Thanks for the link to the chapter. Very interesting reading.
I would not use the word "copy" in comparing the manual process to the filter in PS. Perhaps the idea is the same but the dig*tal world is a different story. Once you start getting close to the sampling resolution the damage to the data is significant.