There are many different ways to tell if your autographed celebrity picture has been legitimately signed by the celebrity, or if it has been forged. Making sure that your copy of an autograph is authentic may be one of the hardest parts of making sure that it is legitimate. However, there are a few methods that will make it easier to tell the difference between a fake autographed photo and a genuine autographed photo.
One method used in faking celebrity autographs is known as: autopen signatures. While it is the celebrity's signature, the celebrity has had little or most cases no contact with the picture at all. An autopen is a machine that takes the celebrity's hand-written signature and inputs it into a template which is saved onto a computer. Any time an autographed photograph is needed of the celebrity, it is simply placed underneath the mechanical arm that then "autographs" the template onto the photo.
Auto-pen signatures for the most part appear to be 100% genuine. However, there are a few signs that you can look for to determine if an autopen method was used.
If the signature appears to be shaky, it may actually be an indication that an auto-pen has been used, as the "shakiness" is an indication of vibrations being sent through the machine. A light color signature is another way to tell if the autograph has been faked. If the autograph seems to be light or sees to have equal pressure distributed through the entire autograph then it is most likely a fake.
Stamped or printed signatures are another method that many forgers use along an autopen signature. These types of signatures generally have the same characteristics as the auto-pen, as they appear to have a drawn on look. Another sign in determining if this method was used is to hold the signature to a light. If the signature glows a shaded purple color then you can almost be certain that the signature was stamped.
Another common way that celebrity autographs have been known to be faked is by use of secretary signatures. These are the hardest to detect because they are usually signed by the celebrity's secretary who has learned to mimic the autograph with great accuracy. One of the best ways to see if this is a forgery is to compare it to other signatures that are owned or that may have been seen.
The best way to compare signatures is to look at them upside down as the mind is not paying attention to what it says, but more as to what it really looks like. Viewing the photo upside down will help point out the more slight differences between the two. Do not automatically assume that when writing a letter to a celebrity that they are going to be the person answering back; usually in these cases the autograph sent is a secretary signature and is not that of the celebrity at all.
The only definite way to know that your copy of a celebrity autograph is legitimate is to be present when the photograph is being signed.