Many years ago I created a genealogy wall, with the images of ancestors, that I have a photographs of. I do not use the original photos 
that I have , since they would be damaged by the sun, but have scanned them into the computer and printed copies of the photos.
I used the smaller size clipboards and painted them with chalkboard paint.
I created labels so the pictures can be easily identified by others and
hung them in family tree formation.
My genealogy wall is often a conversation piece to those that visit our home. 
I do not have all the photos, but I have added over the years, by connecting with family through the internet, and family tree websites.
Maybe in future years I can fill in some of the gaps.