Under US laws, yes the photographer needs a release because there is specific legislation providing the model with a cause of action against the photographer. In Singapore, there is at yet, no cause of action.
Hence, until the courts decide otherwise, no release is needed for use in Singapore.
If the photographer decides to sign something with the model restricting his own use of the photographs, that is his own prerogative.
Counsellor, so, do we or do we not need a release in Singapore? Are you saying, in Singapore, the photographer has the usage rights even without a release?
In the US, the copyrights, without a release, is assumed to be the photographer's. However, the photographer may not use the photo in question if a release is not signed giving the photographer the rights to use the photo. Essentially, you own the photo, but cannot use it. *Using this particular photo for non commercial/self promotion basis, is a very grey area. So, I want a release sign with almost everyone I shoot in the US and Europe. In Asia ... oh well, another grey area.