Whenever single-pixel-accuracy is required, Lens will assist you by magnifying the area around the mouse pointer.
Unlike with many other magnifying tools you don't have to pause during the process of magnification! Lens continually updates its window and always stays on top.
Among many other features it is possible to measure distances between two pixels within the Lens-window.
The magnification factors range from one to ten fold.
A menu pops up when you click on the Lens-window with the right mouse button.