Photographs Of Brazillian Waxing Question About Copyright Of The Photographs Of The Old Painting Of Masterpiece ?

Question about copyright of the photographs of the old painting of masterpiece ? - photographs of brazillian waxing

I want to do a spawning oil painting, including many old photographs of oil paintings. My friend is an artist and has many photos of these paintings. I want to use. But I'm worried about applying copyright law.
There are many sites on the old paintings and I found the pictures are almost identical. Who actually has the copyright? or have permission? I can not believe that the website has received the consent of all of the thousands of photos.
My friend has the collection of these paintings for ten years or more. And he can not remember clearly from. Can I?