>>4364522It entirely depends on what you are going for, but I would say that all the standard qualities of a good photograph still apply.
Sharpness doesn't need to resolve sub micron detail or get absolutely 100% of everything in focus, but it should also not be distracting or take away from the image.
There are parts of this crop from one of my 8x10 shots that are not I'm focus, and it doesn't take away from the image. Also consider that at a 1:1 print the butterfly eye is only about .25 inch tall, so zooming in super close is the equivalent of looking at an enormous print. You can see that the cells of the eye are resolved, but you cannot see them at all on a contact print.
