[header] How to date old photographs [title] Look at dress and hairstyles in the images. [step] If your image has people in it, their hairstyles and clothing styles can be an indicator of the time period. Take a look at clothing catalogs and photographs with known dates. 
These can help you narrow down a timeframe for your image. [substeps] Remember that things like style can be regional, so look for images of people from similar regions or spheres of cultural influence.