> View > Dot for Dot
> what does it do?
If you create a new image and set its dimensions to X by Y inches,
dot-for-dot will make your ruler indicate scale in inches. For millimeters
it will show millimeters/decimetres/centimetres depending on zooming state.
If dot-for-dot is unset, you will get a pixels ruler. That's what it does
as far as I can tell.
Roy S. Schestowitz