[web2py] Edit the regsitration form view and Profile

[dundee]

Hello All,
I am a newbie to web2py. I have edited the User Profile to add fields like 
this: 
auth=Auth(db)
auth.settings.extra_fields['auth_user']= 
[Field('Pic','upload'),Field('About_Me','text')]

This if fine for the Profile view. However, I do not want these fields to 
be available in the registration form. How can I hide these fields from the 
registration for but keep them for the profile view?

Thanks very much for your answers.