Extreme Depth of Field in Night and Macro Photography

For those interested in nightscape photography, has anyone ever given some thoughts to do the same with macro-photography? As we are repeatedly told that closing down a lens aperture begins to somewhat deteriorate from f8 on, where would the optimum picture
quality be reached? How could one find the appropriate quality thresholds by considering: depth of field, distance, aperture, graininess etc?

Also, I was experimenting with this site's depth of field calculator which I assume is giving erroneous results for the hyperfocal distance as seen on the attached example. It has a hyperfocal distance of 26.63 meters, which seems at best out of range for a 25 centimeters camera-object distance.

For macro photography, the same diffraction-limited sharpness criterion applies as with night photography, except macro lenses often "stop down" a little better so the rate of decline in quality is sometimes less.

I took a look at the attachment, and it turns out that the hyperfocal distance listed by the calculator is indeed correct, and is independent of focus distance. It is just the focusing distance that ensures maximal sharpness throughout the image to infinity, given the sharpness criteria. From the hyperfocal distance page though, if your subject is close and there are no objects in the far background then you certainly do not want to use this distance, as it is most applicable to sweeping landscape photos.