With this tool you can calculate how many pixels a star moves on your sensor along RA axis
during one exposure when having the camera on a tripod.
For a wide angle lens it will be very different movement along the DEC axis, it calculate movement at center, top and bottom of sensor along DEC axis.
This is new to me to create pages that do calculation.
I think you must have a HTML5 compatible web browser to use it.
It start to calculate as soon you change or write new figures in the dark red boxes.
Do not exceed the maximum number of characters, delete characters if necessary.