By 'Quick Tool Zoom', I am referring to moving the camera closer to a detail on a Tool in edit mode, NOT the document zoom.
This 'may' be a quicker way to zoom on a precise detail.
While modeling a tool, you normally have to press ALT, click and hold outside the tool, release ALT, and then drag up or down to move the camera in or out. Quite often, you will also have to pan after this process to get the detail you are working on in the center of the view.
There are several key shortcuts you should be aware of:
'0' (zero) will Zoom the document to full (100%) size.
'CTRL-0' zooms to 50% with a unique AA-half mode turned on automatically.
'+' and '-' keys zoom in and out respectively.
'.' key frames the currently visible tool when in edit mode. So if you have moved the camera in to focus on a detail, or if you zoomed way out, this is a quick way to reset the camera to view the entire tool.
Now the tip:
To 'quickly' zoom into a feature on a tool for greater accuracy during sculpting, first position the cursor over the desired point on the tool. Press and hold the '-' key to quickly zoom the document OUT several levels to about -50 to -25%. (YES, you have to zoom OUT, or shrink the DOCUMENT temporarily first.) The more you zoom out, the closer the camera will end up focusing on the area where the cursor is. Now press the '.', and the view will 'tighten' in on the desired region of the tool. Press '0' (zero) key to zoom the document back to 100%. Now you can sculpt fine detail on an area, and when done, press the '.' key again to frame the entire tool in the view once more.
(If the detail area is in the center of the view, you can just press 'CNTL-0' to zoom the document out 50%, '.' to zoom the camera in, and '0' to zoom the doc back to 100%)
Since standard ZBrush interface functions are used, it 'might' be possible that this trick could be turned into a ZPlug that would allow a single short-cut key to perform the whole operation. Maybe even map object zoom and unzoom scripts to the mouse wheel, or else the extra buttons on some mice and on the Wacom Intuos tablets?