Yes, I've used the AutoEnter calc with
Evaluate("Get(CurrentHostTimeStamp)";ModifyTime)
That way I get the Host time stamp rather than the client. Pretty silly that isn't an option for the modification time.
In my example above, ModifyTime is a field that has the local time modification. So any time that record changes at all, the Evaluate will trigger.
So, to your question, you could instead have:
Evaluate("Get(CurrentHostTimeStamp)";Field1)
And it would only trigger when Field1 changed. Note that I believe that will only trigger if it is a local field.