Between 1959 and 1972 there were two types of Hawaiian birth certificates.
The usual type contained the name of the hospital where the birth occurred and was signed by the doctor assisting with the delivery. But because many Hawaiians before statehood had not even had birth certificates, the state allowed a different type of certificate to be created on the testimony of one person.
The "certified copy" of birth certificate presented by Obama so far (and which is apparently the only type of copy that is normally issued now) does not show which of these two types of original birth certificates is in the Hawaiian archives.
If Obama did in fact have one of the types of original birth certificates that did not record a hospital birth, that would raise a lot of questions.
However, I do not believe that the modern certificate presented by the Obama campaign is a "manipulated image", other than the blacking out of the serial number and the fact that it was run through a scanner.
I think three different computer forensic experts have deemed them photo shopped and forgeries!!!