iop

Hi, I have WDS on Win2008 R2. Doing upgrade job on server farm from Win2008 to Win2008 R2. Have built an image as I want it and captured it. When re-imaging the servers that are on the domain they hold their hostname and rejoin fine which is perfect, I just have to change the ip address. But when I use a server that has been removed from the domain and computer account has been deleted or it's just brand new server, then I just get the change Admin password after it's deployed and it's in workgroup. How do I set this up so I can use the same image for existing domain servers and new servers I introduce to this domain? I'm thinking I need to have 2 images one as it is and the other a copy with an answer file. Thanks