I would always recommend some manual calibration beforehand, to learn a bit about how the model works and to get you closer to an acceptable parameter set. Autocalibration without some manual calibration is dangerous, in that it could converge on an inappropriate parameters set.
There is a pretty good chapter on calibration in the swat2009 documentation, &/or look for swat calibration tips on the swat web page.
-- Jim
From: "Somsubhra chattopadhyay" <
som.ag...@gmail.com>
To: "ArcSWAT" <
arc...@googlegroups.com>
Sent: Sunday, November 6, 2011 7:47:56 AM
Subject: [ArcSWAT:3795] Calibration and Validation tips