Previously, the head calibration dialog used standard textboxes and parsed the input assuming that full-stops were used as decimal separators. This was confusing for users when the local number format uses commas as decimal separators, especially as numeric entry in parameter sets is parsed according to the number format specified in the local culture. Head calibration now matches this behaviour.

It previously used 150 dpi (seemed like a good idea at the time) but that produced inappropriately sized bitmaps on most systems (96 dpi is the usual nominal display resolution).