Here is an example of what I do, to paint a work of Art.
First I use my own photographs, unless I am doing a custom piece for a client.
Then I have permission to use their photographs as a reference.
I go from reference photograph, to penciling in the subject, then adding various
mediums until the piece is completed.
Have always found it important to use my own photos. This way, I "should" have no issues in the futures.
What few Silhouettes I have offered for sale are from pieces like this one. My Photograph, my original painting... then blacked out to make a Silhouette. The later has become such an issue the last couple of years, I will not add
any more Silhouettes for sale. It is not worth the hassle and stress in this day and age.