One of the problems that crops up when using "UHPLC" columns and systems to develop methods is the need to modify the conditions for compatibility with older instrumentation. We have put together a spreadsheet that takes some of the sting out of the calculations. The idea is to maintain the same resolution while running at a lower back pressure (and often in a larger column). The price, of course, is a longer run time.

You can download the sheet by clicking on the image here: