No, even if you are doing manual calibration. All modern delta printer firmwares support the M666 command for adjusting the end stop offsets. It helps if you can get the endstop trigger heights within 1mm of each other by adjusting the positions of the endstop switches.
Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod
Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
