Artifacts in photos most likely come from compression. Any photo you see on the internet has been compressed. JPG compression eliminates a lot of information. It also causes a lot of artifacts. For example, a sharp photo of a simple black square on a white background, when compressed as a JPG, shows jagged gray around the edge of the square.
You need access to original analog prints to check for sure.
Artifacts in photos most likely come from compression. Any photo you see on the internet has been compressed. JPG compression eliminates a lot of information. It also causes a lot of artifacts. For example, a sharp photo of a simple black square on a white background, when compressed as a JPG, shows jagged gray around the edge of the square.
You need access to original analog prints to check for sure.
Were they analog actual prints that you saw in person? Or was it online? If it was online, it was compressed, and compression causes artifacts.